Encyclopedia Britannica

<!doctype html> <html lang="en" class="home-desktop ui-ie7 ui-ie"> <head prefix="og: https://ogp.me/ns# fb: https://ogp.me/ns/fb#"> <meta charset="utf-8"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0" /> <link rel="dns-prefetch" href="https://cdn.britannica.com/mendel-resources/3-134"> <link rel="preconnect" href="https://cdn.britannica.com/mendel-resources/3-134"> <link rel="preload" as="script" href="https://www.googletagservices.com/tag/js/gpt.js" /> <link rel="icon" href="/favicon.png" /> <meta name="description" content="Explore the fact-checked online encyclopedia from Encyclopaedia Britannica with hundreds of thousands of objective articles, biographies, videos, and images from experts." /> <meta name="keywords" content="britannica, reference, online, encyclopedia, encyclopaedia, store, dictionary, thesaurus" /> <link rel="canonical" href="https://www.britannica.com/" /> <title>Encyclopedia Britannica | Britannica</title>  <script> !function(){"use strict";function e(e){const t=e.match(/((?=([a-z0-9._!#$%+^&*()[\]<>-]+))\2@[a-z0-9._-]+\.[a-z0-9._-]+)/gi);return t?t[0]:""}function t(t){return e(a(t.toLowerCase()))}function a(e){return e.replace(/\s/g,"")}async function n(e){const t={sha256Hash:"",sha1Hash:""};if(!("msCrypto"in window)&&"https:"===location.protocol&&"crypto"in window&&"TextEncoder"in window){const a=(new TextEncoder).encode(e),[n,c]=await Promise.all([s("SHA-256",a),s("SHA-1",a)]);t.sha256Hash=n,t.sha1Hash=c}return t}async function s(e,t){const a=await crypto.subtle.digest(e,t);return Array.from(new Uint8Array(a)).map(e=>("00"+e.toString(16)).slice(-2)).join("")}function c(e){let t=!0;return Object.keys(e).forEach(a=>{0===e[a].length&&(t=!1)}),t}function i(e,t,a){e.splice(t,1);const n="?"+e.join("&")+a.hash;history.replaceState(null,"",n)}var o={checkEmail:e,validateEmail:t,trimInput:a,hashEmail:n,hasHashes:c,removeEmailAndReplaceHistory:i,detectEmails:async function(){const e=new URL(window.location.href),a=Array.from(e.searchParams.entries()).map(e=>`=`);let s,o;const r=["adt_eih","sh_kit"];if(a.forEach((e,t)=>{const a=decodeURIComponent(e),[n,c]=a.split("=");if("adt_ei"===n&&(s={value:c,index:t,emsrc:"url"}),r.includes(n)){o={value:c,index:t,emsrc:"sh_kit"===n?"urlhck":"urlh"}}}),s)t(s.value)&&n(s.value).then(e=>{if(c(e)){const t={value:e,created:Date.now()};localStorage.setItem("adt_ei",JSON.stringify(t)),localStorage.setItem("adt_emsrc",s.emsrc)}});else if(o){const e={value:{sha256Hash:o.value,sha1Hash:""},created:Date.now()};localStorage.setItem("adt_ei",JSON.stringify(e)),localStorage.setItem("adt_emsrc",o.emsrc)}s&&i(a,s.index,e),o&&i(a,o.index,e)},cb:"adthrive"};const{detectEmails:r,cb:l}=o;r()}(); </script> <script type="text/javascript" data-type="Init Mendel"> window.$UI = {}; window.Constants = {"LICENSE_URL": "/bps/license","DEFAULT_TEST_VERSION": "A","DEFAULT_STATE": "XX","QUIZ_URL": "/quiz","SPOTLIGHT_BROWSE_URL": "/stories/spotlight","CONTENT_TYPE_TEXT": "text/plain;charset=UTF-8","TOPIC_FACTS_DATA_URL": "/facts","QUIZ_BROWSE_IMAGE_QUIZZES": "images","TOPIC_MEDIA_PATH": "/images-videos","USER_PROFILE_URL": "/user","DEBUG_URL": "/debug","ONE_GOOD_FACT_URL": "/one-good-fact","ERROR_404_URL": "/error404","PROCON_CITED_IN_THE_NEWS_URL": "/procon/ProCon-in-the-News","PROCON_URL": "/procon","TOPIC_PAGE_CONTENT_AJAX_URL": "/topic-content/page","INFINITE_SCROLL_PREFIX_URL": "/scroll","TOPIC_TOP_QUESTION_BROWSE_URL": "/questions","CC_USD": "USD","domain": "britannica.com","PROCON_EDITOR_ID": "12941390","SURVEY_URL": "/survey","CATEGORY_BROWSE_URL": "/browse","STORY_BROWSE_URL": "/stories","COUNTRY_US": "US","OPEN_MEDIA_OVERLAY_PARAMETER": "/media","NEWSLETTER_SUBSCRIPTION_URL": "/newsletter-subscription","MAINTENANCE_ERROR_URL": "https://maintenance.eb.com","IMARS_EDITOR_ID": "12365882","PROFILE_EB_EDITOR_URL": "/editor","WEB_INF_RESOURCES_PATH": "WEB-INF/resources","AI_ABOUT_PAGE_URL": "/about-britannica-ai","TOPIC_ADDITIONAL_INFO_PATH": "/additional-info","SUDOKU_GAME_URL": "/games/sudoku","CC_INR": "INR","ARTICLE_PRINT_URL": "/print/article","FIRST_EDITION_URL": "/subscriber/firstedition","WW1_PORTAL_URL": "/discover/World-War-I","MENDEL_COOKIE": "__mendel","topicUrlClasses": "[topic, animal, art, biography, event, place, plant, science, sports, technology, procon, money]","DEMYSTIFIED_BROWSE_URL": "/stories/demystified","LIST_BROWSE_URL": "/list/browse","PROFILE_EXPERT_URL": "/contributor","ASSEMBLY_IMAGE_URL": "/image/assembly","DAY_IN_HISTORY_URL": "/on-this-day","DEFAULT_CURRENCY": "USD","CONTENT_TYPE_XML": "text/xml;charset=UTF-8","PORTAL_FINANCE_BROWSE_URL_PREFIX": "/money/browse","ERROR_400_URL": "/error400","MONEY_IMARS_CATEGORY": "13000","AJAX_PREFIX_URL": "/ajax","TOPIC_BROWSE_URL": "/topic-browse","MARKETING_CONTENT": "/marketing-content","ENV_RUNTIME": "runtime","GALLERY_URL": "/gallery","topicUrlClassesList": "topic|animal|art|biography|event|place|plant|science|sports|technology|procon","CONTENT_TYPE_HTML": "text/html;charset=UTF-8","ENV_LOCAL": "override","MEDIA_OVERLAY_URL": "/media-overlay","CHATBOT_PAGE_URL": "/chatbot","NEWSLETTER_PAGE_URL": "/newsletters","EXPLORE_URL": "/explore","ENV_DEV": "development","MEDIA_URL": "/media","TOPIC_TOP_QUESTION_URL": "/question","PORTAL_FINANCE_URL_PREFIX": "/money","PODCASTS_URL": "/podcasts","STAND_ALONE_VIDEO_URL": "/video","MORE_ON_THIS_DAY_URL": "/more-on-this-day","TOPIC_QUOTES_URL": "/quotes","SEARCH_PAGE_URL": "/search","PROCON_CLASS": "PROCON","KUSTOM_MENDEL_APPLICATION_ID": "1","TOPIC_CONTENT_AJAX_URL": "/topic-content/topic","ENV_BRANCH": "branch","ERROR_URL": "/error","MAIN_VERSION": "mainVersion","TOPIC_COLLECTION_URL": "/summary","LOGINBOX_URL": "/auth/loginbox","PROCON_DEBATE_TOPICS_URL": "/procon/Debate-Topics","ONE_GOOD_FACT_BROWSE_URL": "/one-good-fact/all-good-facts","QUIZ_BROWSE_URL": "/quiz/browse","BIO_BROWSE_URL": "/browse/biographies","LIST_URL": "/list","TIGHTROPE_QUIZ_URL": "/quiz/tightrope","ALPHA_BROWSE_URL": "/sitemap","CONTENT_TYPE_JSON": "application/json","DICTIONARY_URL": "/dictionary","COBRAND_IMAGE_URL": "/image/cobrand","PROCON_IN_THE_NEWS_URL": "/procon/pro-and-con-issues-in-the-news","PROCON_BROWSE_URL": "/procon","QUIZ_BROWSE_VOCAB_QUIZZES": "vocabulary-quizzes","SUBMISSION_URL": "/submission","EB_LOG_OUT": "/auth2/logout","ENV_PRODUCTION": "production","TOPIC_AJAX_URL": "/ajax/topic","TOPIC_SUMMARY_BROWSE_URL": "/summaries","WTFACT_BROWSE_URL": "/stories/wtfact","EXPLORE_OLD_PORTAL_URL": "/explore-old","VIDEO_CHANNEL_URL": "/videos","GALLERY_BROWSE_URL": "/gallery/browse","CACHE_URL": "/cache","PROCON_ABOUT_URL": "/procon/About-ProCon","COMPANION_BROWSE_URL": "/stories/companion","MEDIA_FOLDER": "/eb-media","SHOW_ALL_CONTRIBUTORS": "/additional-info#contributors","BRITANNICA_EDITORS_ID": "4419","ENV_CACHE_DISABLED": "mendelCache","CALCULATORS_BROWSE_URL": "/calculators","STORY_URL": "/story","DEFAULT_COUNTRY": "US","NAVBAR_URL": "/ajax/navbar","EB_LOGIN_URL": "/auth/eb-login","NEW_ARTICLES_URL": "/new-articles",}; window.CDN = "https://cdn.britannica.com"; window.CAM_SETTINGS_URL = "https://cam.britannica.com/settings"; window.CAM_LOGIN_URL = "https://cam.britannica.com/login"; window.CAM_SIGN_UP_URL = "https://cam.britannica.com/registration" window.Mendel = { "config" : { "domain": "britannica.com", "page": "Home", "videoPlayerId": "UyMCoK2v", "sharedUrl": "https://www.britannica.com/", "amuselabsUrl": "https://cdn3.amuselabs.com", "resourcesPrefixUrl": "https://cdn.britannica.com/mendel-resources/3-134/[url]?v=3.134.26", "date": 20250405, "userInfo": { "type": "ANONYMOUS" ,"currency": "AUUS" ,"country": "SG" ,"state": "XX" ,"timezone": "Asia/Singapore" ,"bcomId": "-8724646033870052313" ,"hasAds": true ,"testVersion": "A" ,"adsTestVersion": "A" ,"consumerId": "" ,"instId": "" ,"consumerUserName": "" ,"instUserName": "" ,"cognito": null }, "tvs":{ "r":[25,25,25,25], "a": [25,25,45,5]}, "isLoggedInAsUser": false, "isPhone": false, "isDesktop": true, "logoutUrl": "/auth2/logout", "selfServiceUrl": "https://myaccount.britannica.com", "cdnUrl": "https://cdn.britannica.com", "chatbotApi": "https://www.britannica.com/chat-api", "fetchOffset": 800, "mendelCookieName": "__mendel", "mendelCookie": {"surveyShown":false,"visitedTopicId":0,"currentDate":20250405}, "autocompleteToSearchPage": false }, "GA": {"leg":"A","adLeg":"A","userType":"ANONYMOUS","pageType":"Home","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false,"hasAiTopQuestions":false,"hasSimplifyButton":false} }; </script> <meta property="fb:app_id" content="1887621861548296"/> <meta name="twitter:card" content="summary_large_image" /> <meta name="twitter:site" content="@britannica" /> <meta name="twitter:image" content="https://cdn.britannica.com/mendel-resources/3-134/images/EBLogo.jpg?v=3.134.26" /> <meta name="twitter:description" content="Explore the fact-checked online encyclopedia from Encyclopaedia Britannica with hundreds of thousands of objective articles, biographies, videos, and images from experts."/> <meta property="og:type" content="WEBSITE"/> <meta property="og:title" content="Encyclopedia Britannica | Britannica"/> <meta property="og:description" content="Explore the fact-checked online encyclopedia from Encyclopaedia Britannica with hundreds of thousands of objective articles, biographies, videos, and images from experts."/> <meta property="og:site_name" content="Encyclopedia Britannica" /> <meta property="og:url" content="https://www.britannica.com/"/> <meta property="og:image" content="https://cdn.britannica.com/mendel-resources/3-134/images/EBLogo.jpg?v=3.134.26" /> <meta property="og:image:type" content="" /> <script type="text/javascript" data-type="init opengraph"> Mendel.openGraph = {"type":"WEBSITE","title":"Encyclopedia Britannica","description":"Explore the fact-checked online encyclopedia from Encyclopaedia Britannica with hundreds of thousands of objective articles, biographies, videos, and images from experts.","imageUrl":"https://cdn.britannica.com/mendel-resources/3-134/images/EBLogo.jpg?v=3.134.26","pageUrl":"https://www.britannica.com/"}</script> <link rel="preconnect" href="https://fonts.googleapis.com/"> <link rel="dns-prefetch" href="https://fonts.googleapis.com/" > <link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons"> <link href="https://cdn.britannica.com/mendel-resources/3-134/dist/vendor-bundle.css?v=3.134.26" rel="stylesheet" /> <link href="https://cdn.britannica.com/mendel-resources/3-134/dist/mendel-css.css?v=3.134.26" rel="stylesheet" /> <link href="https://cdn.britannica.com/mendel-resources/3-134/dist/home-page.css?v=3.134.26" rel="stylesheet" /> <script type="text/javascript"> if (self !== top) { top.location = self.location; } </script> <script src="https://cdn.britannica.com/mendel-resources/3-134/js/at.js?v=3.134.26" async ></script> <script> dataLayer = []; </script> <script type="text/javascript">(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start': new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0], j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src= '//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f); })(window,document,'script','dataLayer','GTM-5W6NC8'); </script> </head> <body data-leg="A" class="homepage user-ANONYMOUS user-ads md-desktop leg-a b-ie">  <script>Mendel.config.adProvider='cafemedia';</script> <script data-no-optimize="1" data-cfasync="false"> (function(w, d) { w.adthrive = w.adthrive || {}; w.adthrive.cmd = w. adthrive.cmd || []; w.adthrive.plugin = 'adthrive-ads-manual'; w.adthrive.host = 'ads.adthrive.com';var s = d.createElement('script'); s.async = true; s.referrerpolicy='no-referrer-when-downgrade'; s.src = 'https://' + w.adthrive.host + '/sites/61575e5c934c481d714b3ca9/ads.min.js?referrer=' + w.encodeURIComponent(w.location.href) + '&cb=' + (Math.floor(Math.random() * 100) + 1); var n = d.getElementsByTagName('script')[0]; n.parentNode.insertBefore(s, n); })(window, document); </script> <div class="ie-warning d-flex align-items-center align-self-center justify-content-center site-alert bg-orange"> <div> You are using an <strong>outdated</strong> browser. Please <a class="text-white text-underscore" href="https://browsehappy.com/">upgrade your browser</a> to improve your experience and security. </div> </div> <script id="json-navbar-info" type="application/json"> {"topSectionLinks":[{"title":"Ask the Chatbot","url":"/chatbot","navbarId":"CHATBOT"},{"title":"Games & Quizzes","url":"/quiz/browse","navbarId":"QUIZZES"},{"title":"History & Society","url":"/History-Society","navbarId":"HISTORY"},{"title":"Science & Tech","url":"/Science-Tech","navbarId":"SCIENCE"},{"title":"Biographies","url":"/Biographies","navbarId":"BIOS"},{"title":"Animals & Nature","url":"/Animals-Nature","navbarId":"ANIMALS"},{"title":"Geography & Travel","url":"/Geography-Travel","navbarId":"GEOGRAPHY"},{"title":"Arts & Culture","url":"/Arts-Culture","navbarId":"ART"},{"title":"ProCon","url":"/procon","navbarId":"PROCON"},{"title":"Money","url":"/money","navbarId":"MONEY"},{"title":"Videos","url":"/videos","navbarId":"VIDEOS"}]} </script> <script id="json-hamburger-menu" type="application/json"> {"britannicaMenu1":[{"title":"History & Society","url":"/History-Society"},{"title":"Science & Tech","url":"/Science-Tech"},{"title":"Biographies","url":"/Biographies"},{"title":"Animals & Nature","url":"/Animals-Nature"},{"title":"Geography & Travel","url":"/Geography-Travel"},{"title":"Arts & Culture","url":"/Arts-Culture"},{"title":"ProCon","url":"/procon"},{"title":"Money","url":"/money"}],"britannicaMenu2":[{"title":"Games & Quizzes","url":"/quiz/browse"},{"title":"Videos","url":"/videos"},{"title":"On This Day","url":"/on-this-day"},{"title":"One Good Fact","url":"/one-good-fact"},{"title":"Dictionary","url":"/dictionary"},{"title":"New Articles","url":"/new-articles"}],"browseByCategory":[{"title":{"id":5,"title":"History & Society","url":"/History-Society"},"links":[{"title":"Lifestyles & Social Issues","url":"/browse/Lifestyles-Social-Issues"},{"title":"Philosophy & Religion","url":"/browse/Philosophy-Religion"},{"title":"Politics, Law & Government","url":"/browse/Politics-Law-Government"},{"title":"World History","url":"/browse/World-History"}]},{"title":{"id":6,"title":"Science & Tech","url":"/Science-Tech"},"links":[{"title":"Health & Medicine","url":"/browse/Health-Medicine"},{"title":"Science","url":"/browse/Science"},{"title":"Technology","url":"/browse/Technology"}]},{"title":{"id":3,"title":"Biographies","url":"/Biographies"},"links":[{"title":"Browse Biographies","url":"/browse/biographies"}]},{"title":{"id":1,"title":"Animals & Nature","url":"/Animals-Nature"},"links":[{"title":"Birds, Reptiles & Other Vertebrates","url":"/browse/Birds-Reptiles-Vertebrates"},{"title":"Bugs, Mollusks & Other Invertebrates","url":"/browse/Bugs-Mollusks-Invertebrates"},{"title":"Environment","url":"/browse/Environment"},{"title":"Fossils & Geologic Time","url":"/browse/Fossil-Geologic-Time"},{"title":"Mammals","url":"/browse/Mammals"},{"title":"Plants","url":"/browse/Plants"}]},{"title":{"id":4,"title":"Geography & Travel","url":"/Geography-Travel"},"links":[{"title":"Geography & Travel","url":"/browse/Geography-Travel"}]},{"title":{"id":2,"title":"Arts & Culture","url":"/Arts-Culture"},"links":[{"title":"Entertainment & Pop Culture","url":"/browse/Entertainment-Pop-Culture"},{"title":"Literature","url":"/browse/Literature"},{"title":"Sports & Recreation","url":"/browse/Sports-Recreation"},{"title":"Visual Arts","url":"/browse/Visual-Arts"}]}],"browseByFeature":[{"title":"Companions","url":"/stories/companion"},{"title":"Demystified","url":"/stories/demystified"},{"title":"Image Galleries","url":"/gallery/browse"},{"title":"Lists","url":"/list/browse"},{"title":"Podcasts","url":"/podcasts"},{"title":"Spotlight","url":"/stories/spotlight"},{"title":"Summaries","url":"/summary"},{"title":"Top Questions","url":"/question"},{"title":"#WTFact","url":"/stories/wtfact"}],"moreFromBritannica":[{"title":"Britannica Kids","url":"https://kids.britannica.com/","newTab":true}],"menuType":"DEFAULT"} </script> <header id="header" class="bg-navy-dark"> <div class="global-nav-top-bar"> <div class="grid gx-0 h-100 justify-content-between align-items-center container-lg mx-auto p-0 position-relative"> <div class="d-flex align-items-center"> <button class="d-flex align-items-center justify-self-start js-toggle js-toggle-hamburger btn btn-link link-white btn-sm rounded-0 p-10"> <div class="hamburger-tooltip"> <em class="material-icons d-inline-block font-24" id="nav-toggle" data-icon="menu"></em> </div> <em class="material-icons d-inline-block font-24 global-nav-search-icon d-none" id="nav-search-icon" data-icon="search" ></em> <span id="nav-toggle-text" class="font-14 ml-5 nav-toggle-text">Explore</span> </button> <div class="global-nav-top-search-bar global-nav-top-search-container global-nav-search-container" id="global-nav-top-search-bar"> <form method="get" action="/search" id="global-nav-search" class="md-search-form m-0 global-nav-search-bar-small"> <div class="search-box position-relative col-100"> <label class="sr-only" for="global-nav-search-query">Search Britannica</label> <input name="query" id="global-nav-search-query" placeholder="Search Britannica..." class="form-control form-control-lg rounded-lg font-16 search-query pl-20 pr-70 shadow-sm" maxlength="200" autocomplete="off" aria-label="Search Britannica" /> <button class="search-reset-btn btn btn-link px-10 position-absolute top-0 h-100 d-none" type="reset"> <em class="material-icons" data-icon="close"></em> </button> <button class="search-submit btn btn-link text-blue px-10 position-absolute top-0 right-0 h-100" type="submit" disabled> <span class="sr-only">Click here to search</span> <em class="material-icons search-icon" data-icon="search"></em> </button> </div> </form> </div> <div class="global-nav-top-search-bar global-nav-top-search-container global-nav-search-container" id="global-nav-top-search-bar"> <form method="get" action="/search" id="global-nav-search" class="md-search-form m-0 global-nav-search-bar-small"> <div class="search-box position-relative col-100"> <label class="sr-only" for="global-nav-search-query">Search Britannica</label> <input name="query" id="global-nav-search-query" placeholder="Search Britannica..." class="form-control form-control-lg rounded-lg font-16 search-query pl-20 pr-70 shadow-sm" maxlength="200" autocomplete="off" aria-label="Search Britannica" /> <button class="search-reset-btn btn btn-link px-10 position-absolute top-0 h-100 d-none" type="reset"> <em class="material-icons" data-icon="close"></em> </button> <button class="search-submit btn btn-link text-blue px-10 position-absolute top-0 right-0 h-100" type="submit" disabled> <span class="sr-only">Click here to search</span> <em class="material-icons search-icon" data-icon="search"></em> </button> </div> </form> </div> </div> <img loading="lazy" src="https://cdn.britannica.com/mendel/eb-logo/MendelNewThistleLogo.png" alt="Encyclopedia Britannica" class="global-nav-center global-nav-logo" /> <div class="col-35 col-sm-auto text-right order-3 mr-lg-15 align-items-center d-flex justify-content-end"> <div class="d-none d-md-inline-block"> <SPAN class="marketing-HEADER_SUBSCRIPTION_DESKTOP2 marketing-content" data-marketing-id="HEADER_SUBSCRIPTION_DESKTOP2"><a href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=global-nav&utm_campaign=evergreen-cap" class="subscribe-link btn btn-sm btn-orange py-5 mr-10" target="_blank" rel="noopener"> SUBSCRIBE </a></SPAN></div> <div class="d-inline-block d-md-none mr-5 mr-sm-10"> <SPAN class="marketing-HEADER_SUBSCRIPTION_MOBILE marketing-content" data-marketing-id="HEADER_SUBSCRIPTION_MOBILE"><a href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=global-nav-mobile&utm_campaign=evergreen" class="subscribe-link btn btn-xs btn-orange p-5" target="_blank" rel="noopener"> SUBSCRIBE </a></SPAN></div> <button class="js-toggle-user-dropdown js-toggle btn btn-sm btn-link link-white rounded-0 px-md-15 pl-5 pr-5"> <span class="d-none d-md-inline-block mr-5">Login</span> <em class="material-icons d-inline-block d-md-none font-16 font-sm-20" data-icon="account_circle"></em> <div class="d-none dropdown-menu-subscription-link">https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=nav-login-box&utm_campaign=evergreen</div> <em class="material-icons inactive-icon d-inline-block font-18" data-icon="keyboard_arrow_down"></em> <em class="material-icons active-icon d-inline-block font-18" data-icon="keyboard_arrow_up"></em> </button> </div> </div> </div> <div class="d-none hamburger-menu-subscription-link"><DIV class="marketing-HAMBURGER_MENU_CTA marketing-content" data-marketing-id="HAMBURGER_MENU_CTA"><a href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=hamburger-menu&utm_campaign=evergreen" class="subscribe-link btn btn-sm btn-orange py-5" target="_blank"> SUBSCRIBE </a></DIV></div> <div id="global-nav-react"> <div class="d-none"> <ul> <li><a href="/History-Society">History & Society</a></li> <li><a href="/Science-Tech">Science & Tech</a></li> <li><a href="/Biographies">Biographies</a></li> <li><a href="/Animals-Nature">Animals & Nature</a></li> <li><a href="/Geography-Travel">Geography & Travel</a></li> <li><a href="/Arts-Culture">Arts & Culture</a></li> <li><a href="/procon">ProCon</a></li> <li><a href="/money">Money</a></li> </ul> <ul> <li><a href="/quiz/browse">Games & Quizzes</a></li> <li><a href="/videos">Videos</a></li> <li><a href="/on-this-day">On This Day</a></li> <li><a href="/one-good-fact">One Good Fact</a></li> <li><a href="/dictionary">Dictionary</a></li> <li><a href="/new-articles">New Articles</a></li> </ul> <a href="/History-Society">History & Society</a> <ul> <li><a href="/browse/Lifestyles-Social-Issues">Lifestyles & Social Issues</a></li> <li><a href="/browse/Philosophy-Religion">Philosophy & Religion</a></li> <li><a href="/browse/Politics-Law-Government">Politics, Law & Government</a></li> <li><a href="/browse/World-History">World History</a></li> </ul> <a href="/Science-Tech">Science & Tech</a> <ul> <li><a href="/browse/Health-Medicine">Health & Medicine</a></li> <li><a href="/browse/Science">Science</a></li> <li><a href="/browse/Technology">Technology</a></li> </ul> <a href="/Biographies">Biographies</a> <ul> <li><a href="/browse/biographies">Browse Biographies</a></li> </ul> <a href="/Animals-Nature">Animals & Nature</a> <ul> <li><a href="/browse/Birds-Reptiles-Vertebrates">Birds, Reptiles & Other Vertebrates</a></li> <li><a href="/browse/Bugs-Mollusks-Invertebrates">Bugs, Mollusks & Other Invertebrates</a></li> <li><a href="/browse/Environment">Environment</a></li> <li><a href="/browse/Fossil-Geologic-Time">Fossils & Geologic Time</a></li> <li><a href="/browse/Mammals">Mammals</a></li> <li><a href="/browse/Plants">Plants</a></li> </ul> <a href="/Geography-Travel">Geography & Travel</a> <ul> <li><a href="/browse/Geography-Travel">Geography & Travel</a></li> </ul> <a href="/Arts-Culture">Arts & Culture</a> <ul> <li><a href="/browse/Entertainment-Pop-Culture">Entertainment & Pop Culture</a></li> <li><a href="/browse/Literature">Literature</a></li> <li><a href="/browse/Sports-Recreation">Sports & Recreation</a></li> <li><a href="/browse/Visual-Arts">Visual Arts</a></li> </ul> <ul> <li><a href="/stories/companion">Companions</a></li> <li><a href="/stories/demystified">Demystified</a></li> <li><a href="/gallery/browse">Image Galleries</a></li> <li><a href="/list/browse">Lists</a></li> <li><a href="/podcasts">Podcasts</a></li> <li><a href="/stories/spotlight">Spotlight</a></li> <li><a href="/summary">Summaries</a></li> <li><a href="/question">Top Questions</a></li> <li><a href="/stories/wtfact">#WTFact</a></li> </ul> <ul> <li><a href="https://kids.britannica.com/">Britannica Kids</a></li> </ul> </div> </div> </header> <main> <div class="md-page-wrapper"> <div id="content" class="md-content"> <div class="bg-navy-dark shadow-lg py-5" id="global-nav-homepage-section"> <div class="container-lg"> <div class="grid"> <div class="col-100 col-sm-80 col-sm-offset-10 col-md-50 col-md-offset-25"> <div class="global-nav-home-search-container global-nav-search-container"> <form method="get" action="/search" id="global-nav-search" class="md-search-form m-0 "> <div class="search-box position-relative col-100"> <label class="sr-only" for="global-nav-search-query">Search Britannica</label> <input name="query" id="global-nav-search-query" placeholder="Search Britannica..." class="form-control form-control-lg rounded-lg font-16 search-query pl-20 pr-70 shadow-sm" maxlength="200" autocomplete="off" aria-label="Search Britannica" /> <button class="search-reset-btn btn btn-link px-10 position-absolute top-0 h-100 d-none" type="reset"> <em class="material-icons" data-icon="close"></em> </button> <button class="search-submit btn btn-link text-blue px-10 position-absolute top-0 right-0 h-100" type="submit" disabled> <span class="sr-only">Click here to search</span> <em class="material-icons search-icon" data-icon="search"></em> </button> </div> </form> </div> </div> </div> </div> <div class="container-lg p-0 d-flex justify-content-center overflow-hidden"> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 mt-20 global-nav-slider category-snap-slider"> <div class="slider-container js-slider-container overflow-hidden d-flex font-14 overflow-hidden text-nowrap mx-5"> <a class="nav-bar-category mx-5 category-link-CHATBOT" href="/chatbot">Ask the Chatbot</a> <a class="nav-bar-category mx-5 category-link-QUIZZES" href="/quiz/browse">Games & Quizzes</a> <a class="nav-bar-category mx-5 category-link-HISTORY" href="/History-Society">History & Society</a> <a class="nav-bar-category mx-5 category-link-SCIENCE" href="/Science-Tech">Science & Tech</a> <a class="nav-bar-category mx-5 category-link-BIOS" href="/Biographies">Biographies</a> <a class="nav-bar-category mx-5 category-link-ANIMALS" href="/Animals-Nature">Animals & Nature</a> <a class="nav-bar-category mx-5 category-link-GEOGRAPHY" href="/Geography-Travel">Geography & Travel</a> <a class="nav-bar-category mx-5 category-link-ART" href="/Arts-Culture">Arts & Culture</a> <a class="nav-bar-category mx-5 category-link-PROCON" href="/procon">ProCon</a> <a class="nav-bar-category mx-5 category-link-MONEY" href="/money">Money</a> <a class="nav-bar-category mx-5 category-link-VIDEOS" href="/videos">Videos</a> </div> <button disabled class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-blue " aria-label="Previous"> <span class="material-icons md-24" data-icon="keyboard_arrow_left"></span> </button> <button disabled class="next-button js-next-button position-absolute btn btn-circle shadow btn-blue " aria-label="Next"> <span class="material-icons md-24" data-icon="keyboard_arrow_right"></span> </button> </div> </div> </div> <div id="homepage-content" itemscope itemtype="https://schema.org/Organization"> <meta itemprop="url" content="https://www.britannica.com" /> <meta itemprop="logo" content="https://cdn.britannica.com/mendel-resources/3-134/images/EBLogo.jpg?v=3.134.26" /> <meta itemprop="name" content="Encyclopedia Britannica" /> <meta itemprop="description" content="Explore the fact-checked online encyclopedia from Encyclopaedia Britannica with hundreds of thousands of objective articles, biographies, videos, and images from experts." /> <DIV class="marketing-HOMEPAGE_HERO_BANNER marketing-content" data-marketing-id="HOMEPAGE_HERO_BANNER"> <a class="d-block container gtm-homepage-hero-banner-promo" href="/sports/Olympic-Games"> <picture style="display:flex;justify-content: center;width:100%;"> <source media="(min-width:1100px)" srcset="https://cdn.britannica.com/marketing/webby-video-vote-promo-desktop.jpg"> <source media="(min-width:780px)" srcset="https://cdn.britannica.com/marketing/webby-video-vote-promo-tablet.jpg"> <img src="https://cdn.britannica.com/marketing/webby-video-vote-promo-mobile.jpg" alt="Banner with text Watch our Webby-nominated video! and a Learn More button, featuring a skateboarder on a colorful background."object-fit: cover; width:100%;"> </picture> </a></DIV><div class="container"> <div class="kic-container qa-contentful1 my-20 "> <div class="label mb-10"> <a href="/on-this-day" > April 5, 2025 </a> </div> <div class="cards3up kic-grid-A1"> <div class="kic-title-container"> <h2 class="display-3 font-serif kic-title mb-15"> <a href="https://www.britannica.com/sports/March-Madness-Mascot-Challenge" class="md-crosslink " data-show-preview="true">Mascot Madness</a> </h2> <div class="font-serif"> This weekend marks <a href="https://www.britannica.com/sports/March-Madness" class="md-crosslink " data-show-preview="true">the pinnacle of college basketball</a> as the Final Four battle to determine the last team standing. The <a href="https://www.britannica.com/news/1328156/11166d6bc6d631170e57f740aa1731b1" class="md-crosslink " data-show-preview="true">women’s side features</a> the <a href="https://www.britannica.com/topic/University-of-California" class="md-crosslink " data-show-preview="true">UCLA Bruins</a>, <a href="https://www.britannica.com/topic/University-of-Texas" class="md-crosslink " data-show-preview="true">Texas Longhorns</a>, <a href="https://www.britannica.com/topic/University-of-South-Carolina" class="md-crosslink " data-show-preview="true">South Carolina Gamecocks</a>, and <a href="https://www.britannica.com/topic/University-of-Connecticut" class="md-crosslink " data-show-preview="true">UConn Huskies</a>, while the men’s teams are the <a href="https://www.britannica.com/topic/University-of-Florida" class="md-crosslink " data-show-preview="true">Florida Gators</a>, <a href="https://www.britannica.com/topic/Auburn-University" class="md-crosslink " data-show-preview="true">Auburn Tigers</a>, <a href="https://www.britannica.com/topic/Duke-University" class="md-crosslink " data-show-preview="true">Duke Blue Devils</a> and <a href="https://www.britannica.com/topic/University-of-Houston" class="md-crosslink " data-show-preview="true">Houston Cougars</a>. Although you can’t control the action on the court, you can determine which mascot is best by voting in our <a href="https://www.britannica.com/sports/March-Madness-Mascot-Challenge" class="md-crosslink " data-show-preview="true">March Madness Mascot Challenge</a>. </div> </div> <div class="card-hero"> <div class="card "> <div class="card-media media-IMAGE"> <a class="position-relative w-100" href="/sports/March-Madness-Mascot-Challenge"> <img loading="eager" src="https://cdn.britannica.com/43/270843-050-7BA9804D/march-madness-bracket-2025.jpg?w=4000&h=2260&c=crop" alt="March Madness Bracket 2025 art" class="w-100 " /> </a> </div> <div class="card-body mt-10 p-0"> <a class="font-weight-bold h5" href="/sports/March-Madness-Mascot-Challenge">Vote Today to Determine the Last Mascot Standing</a> <div class="credit mt-5" style="word-break: break-word;">Encyclopædia Britannica, Inc.</div> </div> </div> </div> <div class="card-2"> <div class="card card-horizontal card-sm-vertical"> <div class="card-media media-VIDEO"> <div data-type="video" class="position-relative w-100"> <img loading="eager" src="https://cdn.britannica.com/20/239220-138-58B2E6CD/March-Madness-basketball.jpg?w=354&h=300&c=crop&q=80" alt="Did You Know? March Madness. Learn about how March Madness became synonymous with basketball." class="w-100" /> <div class="btn btn-link link-white position-absolute" style="left: 50%; top: 50%; transform: translate3d(-50%, -50%, 0)"> <em class="material-icons display-1" data-icon="play_circle_outline"></em> </div> <script type="application/json"> { "sources": [ { "file" : "//content.jwplatform.com/manifests/s3eKNDBO.m3u8" } ], "image": "https://cdn.britannica.com/20/239220-138-58B2E6CD/March-Madness-basketball.jpg", "tracks": [ { "file" : "//assets-jpcust.jwpsrv.com/tracks/AtoSC0tp", "label": "English" } ] } </script> </div> </div> <div class="card-body mt-10 p-0"> <a class="font-weight-bold h5" href="/sports/March-Madness">How March Madness Made College Basketball an American Obsession</a> <div class="credit mt-5" style="word-break: break-word;">Encyclopædia Britannica, Inc.</div> </div> </div> </div> <div class="card-3"> <div class="card card-horizontal card-sm-vertical"> <div class="card-media media-IMAGE"> <a class="position-relative w-100" href="/list/the-10-greatest-basketball-players-of-all-time"> <img loading="eager" src="https://cdn.britannica.com/37/3837-004-6841BB67/Bill-Russell.jpg?w=354&h=300&c=crop&q=80" alt="Bill Russell, mid-1960s. Basketball player with the Boston Celtics" class="w-100 " /> </a> </div> <div class="card-body mt-10 p-0"> <a class="font-weight-bold h5" href="/list/the-10-greatest-basketball-players-of-all-time">The 10 Greatest Basketball Players of All Time</a> <div class="credit mt-5" style="word-break: break-word;">Dick Raphael</div> </div> </div> </div> <div class="read-more"> <h3>Discover More</h3> <div class="grid"> <div class="col-sm-50 mb-15 mb-sm-0"> <a class="font-16 font-weight-bold" href="/story/why-are-basketball-hoops-10-feet-high">Why Are Basketball Hoops 10 Feet High?</a> </div> <div class="col-sm-50 mb-15 mb-sm-0"> <a class="font-16 font-weight-bold" href="https://www.britannica.com/sports/basketball#ref29665" target="_blank">The Origin and Evolution of Basketball</a> </div> </div> </div> <div class="kic-right-rail kic-right-rail-A1 font-14"> <div class="feature-block "><div class="oyr-title-container"><h3 class="h2 oyr-title font-serif mb-15"> <a href="https://www.britannica.com/topic/news-agency" class="md-crosslink " data-show-preview="true">Behind the Headlines</a> </h3><p class="font-serif mb-20">A technology titan celebrates its golden anniversary, and a giant life-saving rat sets a world record.</p></div> <a class="oyr-link-title font-weight-bold d-block mb-10" href="/money/Microsoft-Corporation">Microsoft turns 50</a><p class="font-serif mb-20">On April 4, 1975, <a href="https://www.britannica.com/money/Bill-Gates" class="md-crosslink " data-show-preview="true">Bill Gates</a> and <a href="https://www.britannica.com/money/Paul-Allen" class="md-crosslink " data-show-preview="true">Paul Allen</a>, two <a href="https://www.britannica.com/news/380624/dd33373215f6d22ccf4faa2913f6075f" class="md-crosslink " data-show-preview="true">boyhood friends from Seattle, founded Microsoft</a>, deriving the name from the words <em>microcomputer</em> and <em>software</em>. Their first success that year was in converting <a href="https://www.britannica.com/technology/BASIC" class="md-crosslink " data-show-preview="true">BASIC</a>, a popular mainframe <a href="https://www.britannica.com/list/influential-computer-programming-languages" class="md-crosslink " data-show-preview="true">computer programming language</a>, for use on an early personal computer, <a href="https://www.britannica.com/technology/computer/The-personal-computer-revolution#ref724528" class="md-crosslink " data-show-preview="true">the Altair</a>. In 1980 <a href="https://www.britannica.com/money/International-Business-Machines-Corporation" class="md-crosslink " data-show-preview="true">IBM</a> asked <a href="https://www.britannica.com/money/Microsoft-Corporation" class="md-crosslink " data-show-preview="true">Microsoft</a> to create the <a href="https://www.britannica.com/technology/operating-system" class="md-crosslink " data-show-preview="true">operating system</a> for its first <a href="https://www.britannica.com/technology/personal-computer" class="md-crosslink " data-show-preview="true">personal computer</a> (pictured below), and the rest is history.</p> <a href="https://www.britannica.com/technology/personal-computer#ref61213" target="_blank"><img src="https://cdn.britannica.com/08/23608-002-B0678D61/IBM-Personal-Computer-machine-Microsoft-MS-DOS-operating-1981.jpg?w=630" loading="eager" alt="IBM Personal Computer, 1981" class="d-block oyr-img mb-15 border-sm rounded-sm"></a> <a class="oyr-link-title font-weight-bold d-block mb-10" href="https://www.britannica.com/video/rats-land-mines/-194023" target="_blank">Rats that save lives</a><p class="font-serif mb-20">You may be familiar with <a href="https://www.britannica.com/story/working-like-a-dog-7-animals-with-jobs" class="md-crosslink " data-show-preview="true">bomb-sniffing dogs and dolphins</a>, but a giant rat? Ronin, a <a href="https://www.britannica.com/technology/land-mine" class="md-crosslink " data-show-preview="true">land mine</a>-sniffing rodent, recently located his 109th land mine, landing the <a href="https://www.britannica.com/animal/African-pouched-rat" class="md-crosslink " data-show-preview="true">African giant pouched rat</a> into <a href="https://www.britannica.com/topic/The-Guinness-Book-of-World-Records" class="md-crosslink " data-show-preview="true"><em>The Guinness Book of World Records</em></a> as the most successful mine-detection rat in history, according to Belgian nonprofit APOPO. Also known as the <a href="https://www.britannica.com/animal/African-pouched-rat" class="md-crosslink " data-show-preview="true">Gambian pouched rat</a> (pictured below), these rats are <a href="https://www.britannica.com/video/rats-land-mines/-194023" class="md-crosslink " data-show-preview="true">in high demand in Asia and Africa</a>, where land mines kill or maim thousands of people each year. They can cover more ground than humans and because they’re relatively small, there’s no worry that they will set off a land mine.</p> <a href="/animal/African-pouched-rat"><img src="https://cdn.britannica.com/24/271224-002-5910666D/APOPO-African-giant-pouched-rat-trained-to-detect-tuberculosis.jpg?w=630" loading="eager" alt="Carolina - an African giant pouched rat - shown at work sniffing a hole above a heat-inactivated sample to identify tuberculosis in an APOPO lab in Tanzania. Carolina is sniffing sputum samples to detect possible cases of tuberculosis (TB). Carolina is trained to check TB samples collected from local clinics. Any samples they indicate as suspect are reconfirmed in APOPO's lab using WHO-endorsed methods. Carolina was retired in November 2024 after saving human lives by detecting more than 3,000 cases of TB. Photo from 2018" class="d-block oyr-img mb-15 border-sm rounded-sm"></a> <div class="credit">IBM Archives, © APOPO</div></div> </div> </div> </div> </div> <div class="container trending-content my-40"> <h2 class="mb-15">Popular on <span>Britannica</span></h2> <div class="grid"> <div class="trending-list-container qa-treading-articles col-100 col-md-33 mb-30 mb-md-0"> <div class="Articles border-top-5"></div> <div class="border border-top-0 p-20 py-10 rounded-bl-lg rounded-br-lg"> <h3 class="font-16 text-uppercase mb-15 mb-md-20 d-block">Articles</h3> <ol class="list-none"> <li > <a class="d-block my-10 my-md-15" href="https://www.britannica.com/topic/Smoot-Hawley-Tariff-Act">Smoot-Hawley Tariff Act</a> </li> <li > <a class="d-block my-10 my-md-15" href="https://www.britannica.com/animal/list-of-insects-2073946">list of insects</a> </li> <li > <a class="d-block my-10 my-md-15" href="https://www.britannica.com/biography/Anwar-Ibrahim">Anwar Ibrahim</a> </li> <li > <a class="d-block my-10 my-md-15" href="https://www.britannica.com/animal/list-of-rodents-2057092">list of rodents</a> </li> <li > <a class="d-block my-10 my-md-15" href="https://www.britannica.com/topic/April-Fools-Day">April Fools’ Day</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="https://www.britannica.com/topic/Mandaeanism">Mandaeanism</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="https://www.britannica.com/topic/Tariff-of-1828">Tariff of 1828</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="https://www.britannica.com/place/Pacific-Islands">Pacific Islands</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="https://www.britannica.com/procon/zoos-debate">Zoos</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="https://www.britannica.com/event/Oklahoma-City-bombing">Oklahoma City bombing</a> </li> </ol> <div class="text-center mt-15 mt-md-20"> <button class="trending-show btn btn-sm btn-outline-blue border"> <span class="button-content">Show More <span class="material-icons" data-icon="expand_more"></span></span> <span class="button-content d-none">Show Less <span class="material-icons" data-icon="expand_less"></span></span> </button> </div> </div> </div> <div class="trending-list-container qa-treading-features col-100 col-md-33 mb-30 mb-md-0"> <div class="Features border-top-5"></div> <div class="border border-top-0 p-20 py-10 rounded-bl-lg rounded-br-lg"> <h3 class="font-16 text-uppercase mb-15 mb-md-20 d-block">Features</h3> <ol class="list-none"> <li > <a class="d-block my-10 my-md-15" href="/story/what-is-an-aftershock">What Is an Aftershock?</a> </li> <li > <a class="d-block my-10 my-md-15" href="/story/whats-inside-the-pyramid-at-chichn-itz">What’s Inside the Pyramid at Chichén Itzá?</a> </li> <li > <a class="d-block my-10 my-md-15" href="/story/causes-of-the-great-depression">Causes of the Great Depression</a> </li> <li > <a class="d-block my-10 my-md-15" href="/story/is-australia-an-island">Is Australia an Island?</a> </li> <li > <a class="d-block my-10 my-md-15" href="/story/7-of-the-worlds-most-poisonous-mushrooms">7 of the World’s Most Poisonous Mushrooms</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/story/which-religion-is-the-oldest">Which Religion Is the Oldest?</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/story/who-really-invented-baseball">Who Really Invented Baseball?</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/story/the-time-julius-caesar-was-captured-by-pirates">The Time Julius Caesar Was Captured by Pirates</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/story/why-does-the-new-year-start-on-january-1">Why Does the New Year Start on January 1? </a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/story/where-do-anti-semitic-conspiracy-theories-about-the-rothschild-family-come-from">Where Do Antisemitic Conspiracy Theories About the Rothschild Family Come From?</a> </li> </ol> <div class="text-center mt-15 mt-md-20"> <button class="trending-show btn btn-sm btn-outline-blue border"> <span class="button-content">Show More <span class="material-icons" data-icon="expand_more"></span></span> <span class="button-content d-none">Show Less <span class="material-icons" data-icon="expand_less"></span></span> </button> </div> </div> </div> <div class="trending-list-container qa-treading-lists col-100 col-md-33 mb-30 mb-md-0"> <div class="Lists border-top-5"></div> <div class="border border-top-0 p-20 py-10 rounded-bl-lg rounded-br-lg"> <h3 class="font-16 text-uppercase mb-15 mb-md-20 d-block">Lists</h3> <ol class="list-none"> <li > <a class="d-block my-10 my-md-15" href="/list/new-seven-wonders-of-the-world">New Seven Wonders of the World</a> </li> <li > <a class="d-block my-10 my-md-15" href="/list/the-10-greatest-basketball-players-of-all-time">The 10 Greatest Basketball Players of All Time</a> </li> <li > <a class="d-block my-10 my-md-15" href="/list/9-worst-generals-in-history">9 Worst Generals in History</a> </li> <li > <a class="d-block my-10 my-md-15" href="/list/korean-war-timeline">Korean War Timeline</a> </li> <li > <a class="d-block my-10 my-md-15" href="/list/6-deadliest-earthquakes">The 6 Deadliest Earthquakes Since 1950</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/list/all-119-references-in-we-didnt-start-the-fire-explained">All 119 References in “We Didn’t Start the Fire,” Explained</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/list/10-classical-music-composers-to-know">10 Classical Music Composers to Know</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/list/weapons-of-world-war-i">Weapons of World War I</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/list/10-of-the-worlds-most-dangerous-fish">10 of the World’s Most Dangerous Fish</a> </li> <li class="after5 d-none"> <a class="d-block my-10 my-md-15" href="/list/7-of-historys-most-notorious-serial-killers">7 of History's Most Notorious Serial Killers</a> </li> </ol> <div class="text-center mt-15 mt-md-20"> <button class="trending-show btn btn-sm btn-outline-blue border"> <span class="button-content">Show More <span class="material-icons" data-icon="expand_more"></span></span> <span class="button-content d-none">Show Less <span class="material-icons" data-icon="expand_less"></span></span> </button> </div> </div> </div> </div> </div> <div class="gtm-money-cta container"> <div class="grid mb-10"> <div class="col-100 col-sm-30 col-md-25 col-lg-25 col-xl-25 text-left mb-10 mt-10"> <a class="gtm-money-cta-logo" href="https://www.britannica.com/money"> <img class="col-65 col-sm-90 col-md-90 col-lg-95 col-xl-100" src="https://cdn.britannica.com/money/assets/britannica-money-global-nav-logo-250x30-2x.png" alt="Britannica Money"> </a> </div> <div class=" text-center pt-15"> <a class="gtm-money-cta-nav-link link-blue-dark" href="/money/browse/investing">Investing</a> </div> <div class=" text-center pt-15"> <a class="gtm-money-cta-nav-link link-blue-dark" href="/money/browse/Trading">Trading</a> </div> <div class=" text-center pt-15"> <a class="gtm-money-cta-nav-link link-blue-dark" href="/money/browse/retirement">Retirement</a> </div> <div class=" text-center pt-15"> <a class="gtm-money-cta-nav-link link-blue-dark" href="/money/browse/household-finance">Household Finance</a> </div> <div class=" text-center pt-15"> <a class="gtm-money-cta-nav-link link-blue-dark" href="/money/browse/history-and-theory">Finance & the Economy</a> </div> <div class=" text-center pt-15"> <a class="gtm-money-cta-nav-link link-blue-dark" href="/money/browse/Companies">Companies</a> </div> </div> <div class="grid"> <div class="gtm-money-cta-card col-100 p-10 col-md-25"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.britannica.com/money/trade-war-meaning" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/03/265903-004-5390FAB0/Trade-Policy-Photo-Illustration-image-Brick-wall-made-of-hundred-dollar-bills.jpg?w=400&h=225&c=crop" alt="Brick wall made of hundred dollar bills." class="w-100" /> </div> </a> </div> <div class="card-body w-100 money-card"> <a href="https://www.britannica.com/money/trade-war-meaning" class="title font-weight-bold font-16">When trade policy turns contentious: Tariffs, currency devaluation, and other trade barriers</a> </div> </div> </div> <div class="gtm-money-cta-card col-100 p-10 col-md-25"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.britannica.com/money/cboe-volatility-index" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/09/265709-050-11F07D26/vix-spikes-and-valleys-graph.jpg?w=400&h=225&c=crop" alt="A price chart shows spikes in market volatility from 2007 to 2024." class="w-100" /> </div> </a> </div> <div class="card-body w-100 money-card"> <a href="https://www.britannica.com/money/cboe-volatility-index" class="title font-weight-bold font-16">What kind of mood is the market in? Check the Cboe Volatility Index (VIX)</a> </div> </div> </div> <div class="gtm-money-cta-card col-100 p-10 col-md-25"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.britannica.com/money/sequence-of-returns-risk" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/99/258999-159-1D93EA5D/Financial-candlestick-chart-on-touchscreen.jpg?w=400&h=225&c=crop" alt="Financial candlestick chart on touchscreen." class="w-100" /> </div> </a> </div> <div class="card-body w-100 money-card"> <a href="https://www.britannica.com/money/sequence-of-returns-risk" class="title font-weight-bold font-16">Understanding sequence risk and its impact on your retirement savings</a> </div> </div> </div> <div class="gtm-money-cta-card col-100 p-10 col-md-25"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.britannica.com/money/cost-to-file-taxes" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/49/254849-050-58F25486/US-Federal-Tax-Return-Form-1040-and-Calculator-Concept-of-Form-1040-Individual-Income-Tax-Return.jpg?w=400&h=225&c=crop" alt="US Federal Tax Return Form 1040, a calculator, and some cash." class="w-100" /> </div> </a> </div> <div class="card-body w-100 money-card"> <a href="https://www.britannica.com/money/cost-to-file-taxes" class="title font-weight-bold font-16">Filing your taxes: Answers to 6 frequently asked questions</a> </div> </div> </div> </div> </div> <div class="qa-contentful2"> <div class="container my-40"> <div class="mb-15"> <h2> <a href="https://www.britannica.com/new-articles" class="md-crosslink " data-show-preview="true">New on <em>Britannica</em></a> </h2> </div> <div class="grid g-20 mb-20 gtm-homepage-editors-picks"> <div class="col-100 col-sm-50 col-md"> <div class="card card-base col-100"> <div class="card-media"> <a href="/topic/Do-Cows-Pollute-as-Much-as-Cars" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/50/161650-004-01A9C52C/Group-Waltshire-cows-England.jpg?w=400&h=225&c=crop" alt="Group of black and white cows in a pasture, Waltshire, England." class="w-100" /> </div> </a> </div> <div class="card-body w-100 font-serif font-14 homepage2up-card"> <a href="/topic/Do-Cows-Pollute-as-Much-as-Cars" class="title font-weight-bold font-16">Pollution: cows vs. cars</a> <div class="m-0 mt-5 description "> Cows are notorious for their emissions of <a href="https://www.britannica.com/science/methane" class="md-crosslink " data-show-preview="true">methane</a>. How does that compare to the <a href="https://www.britannica.com/science/carbon-dioxide" class="md-crosslink " data-show-preview="true">carbon dioxide</a> emissions from gas-powered cars? </div> </div> </div> </div> <div class="col-100 col-sm-50 col-md"> <div class="card card-base col-100"> <div class="card-media"> <a href="/animal/desert-tarantula" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/31/158431-004-B4424EB9/Desert-tarantula.jpg?w=400&h=225&c=crop" alt="Desert tarantula." class="w-100" /> </div> </a> </div> <div class="card-body w-100 font-serif font-14 homepage2up-card"> <a href="/animal/desert-tarantula" class="title font-weight-bold font-16">Desert tarantula</a> <div class="m-0 mt-5 description "> This large hairy North American spider with a <a href="https://www.britannica.com/science/venom" class="md-crosslink " data-show-preview="true">venomous</a> bite is native to the southwest U.S. and northern Mexico. </div> </div> </div> </div> <div class="col-100 col-sm-50 col-md"> <div class="card card-base col-100"> <div class="card-media"> <a href="/topic/Who-Invented-the-High-Five" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/15/237515-004-12AEECBA/Kids-Playing-Soccer-two-girls-giving-a-high-five.jpg?w=400&h=225&c=crop" alt="Kids Playing Soccer - two girls in blue t-shirts giving a high five." class="w-100" /> </div> </a> </div> <div class="card-body w-100 font-serif font-14 homepage2up-card"> <a href="/topic/Who-Invented-the-High-Five" class="title font-weight-bold font-16">Who invented the high five?</a> <div class="m-0 mt-5 description "> The high five is one of the most popular gestures in the world, often used in a celebratory manner. How did it start? </div> </div> </div> </div> <div class="col-100 col-sm-50 col-md"> <div class="card card-base col-100"> <div class="card-media"> <a href="/topic/Symbols-on-a-US-Dollar-Bill" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/51/269051-004-C8B49824/the-reverse-of-the-great-seal-of-the-united-states-dollar-bill.jpg?w=400&h=225&c=crop" alt="The reverse of the Great Seal of the United States, as shown on the back of the dollar bill." class="w-100" /> </div> </a> </div> <div class="card-body w-100 font-serif font-14 homepage2up-card"> <a href="/topic/Symbols-on-a-US-Dollar-Bill" class="title font-weight-bold font-16">The symbols on a dollar bill</a> <div class="m-0 mt-5 description "> This interactive explores the deeper meaning of the symbols on the U.S. <a href="https://www.britannica.com/money/dollar" class="md-crosslink " data-show-preview="true">dollar</a>, which tell a story all their own. </div> </div> </div> </div> </div> </div> </div> <div class="container my-40 qa-homepage-procon"> <div class="mb-15"> <h2><a href="/procon">Popular ProCon Debate Topics</a></h2> </div> <div class="grid g-20 mb-20"> <div class="col-100 col-sm-50 col-md"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.britannica.com/procon/single-use-plastics-debate" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/10/260710-050-DA1C481F/Fruit-coolers-cocktails-for-sale-market-Barcelona-Spain.jpg?w=400&h=225&c=crop" alt="Fruit desserts" class="w-100" /> </div> </a> </div> <div class="card-body w-100 font-serif font-14 procon-card"> <a href="https://www.britannica.com/procon/single-use-plastics-debate" class="title font-weight-bold font-16">Single-Use Plastics</a> <div class="m-0 mt-5 description "> Should Single-Use Plastics Be Banned? </div> </div> </div> </div> <div class="col-100 col-sm-50 col-md"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.britannica.com/procon/artificial-intelligence-AI-debate" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/46/226046-050-9C554901/3d-rendering-closeup-AI-robot-face-with-front-view-Location-Japan-.jpg?w=400&h=225&c=crop" alt="Artificial intelligence" class="w-100" /> </div> </a> </div> <div class="card-body w-100 font-serif font-14 procon-card"> <a href="https://www.britannica.com/procon/artificial-intelligence-AI-debate" class="title font-weight-bold font-16">Artificial Intelligence (AI)</a> <div class="m-0 mt-5 description "> Is Artificial Intelligence Good for Society? </div> </div> </div> </div> <div class="col-100 col-sm-50 col-md"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.britannica.com/procon/reparations-for-slavery-debate" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/26/264926-050-9CDD5365/Slave-reparations-demonstration-National-Mall-Washington-DC.jpg?w=400&h=225&c=crop" alt="Slave reparations" class="w-100" /> </div> </a> </div> <div class="card-body w-100 font-serif font-14 procon-card"> <a href="https://www.britannica.com/procon/reparations-for-slavery-debate" class="title font-weight-bold font-16">Reparations for Slavery</a> <div class="m-0 mt-5 description "> Should the U.S. Pay Reparations to the Descendants of Slaves? </div> </div> </div> </div> <div class="col-100 col-sm-50 col-md"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.britannica.com/procon/TikTok-debate" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/11/229611-050-12DA5A8F/TikTok-app-smartphone.jpg?w=400&h=225&c=crop" alt="TikTok" class="w-100" /> </div> </a> </div> <div class="card-body w-100 font-serif font-14 procon-card"> <a href="https://www.britannica.com/procon/TikTok-debate" class="title font-weight-bold font-16">TikTok</a> <div class="m-0 mt-5 description "> Should TikTok Be Banned? </div> </div> </div> </div> </div> </div> <div class="container qa-featured-games my-40"> <h2 class="mt-20 mb-15 d-inline-block">Featured Games</h2> <a href="/quiz/browse#featured-games" class="font-weight-bold ml-10 font-14">See All</a> <div class="featured-games-container"> <div class="primary-featured-game-card"> <div class="card card-base col-100"> <div class="card-media"> <a href="https://www.merriam-webster.com/games/quordle" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/quordle.jpeg?w=400&h=300&c=crop" alt="Quordle" class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="https://www.merriam-webster.com/games/quordle" class="title font-weight-bold font-16">Quordle</a> <div class="m-0 mt-5 description "> Can you solve four words at once? </div> </div> </div> </div> <div class="featured-games-grid"> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/quiz/tightrope"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/tightrope_promo_4_3_2x.webp?w=100&h=75&c=crop" alt="Tightrope" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/quiz/tightrope" >Tightrope</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">A daily trivia game</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.merriam-webster.com/games/blossom-word-game"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/blossom1x.jpeg?w=100&h=75&c=crop" alt="Blossom" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.merriam-webster.com/games/blossom-word-game" >Blossom</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Pick the best words</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/games/octordle"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/octordle-4x3.png?w=100&h=75&c=crop" alt="Octordle" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/games/octordle" >Octordle</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">The party starts at eight</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.merriam-webster.com/games/pilfer"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/pilfer.png?w=100&h=75&c=crop" alt="Pilfer" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.merriam-webster.com/games/pilfer" >Pilfer</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">A delightful ruthless word game</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.merriam-webster.com/games/missing-letter"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/missingLetter.png?w=100&h=75&c=crop" alt="The Missing Letter" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.merriam-webster.com/games/missing-letter" >The Missing Letter</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">A daily crossword with a twist</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.merriam-webster.com/games/twofer-goofer"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/twofer-goofer.png?w=100&h=75&c=crop" alt="Twofer Goofer" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.merriam-webster.com/games/twofer-goofer" >Twofer Goofer</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Think you know it, poet?</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/games/victordle/"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/victordle.png?w=100&h=75&c=crop" alt="Victordle" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/games/victordle/" >Victordle</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Play head-to-head!</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/games/sudoku"> <img loading="lazy" src="https://cdn.britannica.com/kstm/GAME/sudoku_Icon1.png?w=100&h=75&c=crop" alt="Sudoku" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/games/sudoku" >Sudoku</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Your daily logic challenge</div> </div> </div> </div> </div> </div> <div class="container qa-quizzes my-40"> <h2 class="mt-20 mb-15 d-inline-block">Trending Quizzes</h2> <a href="/quiz/browse" class="font-weight-bold ml-10 font-14">See All Quizzes</a> <div class="m-n10 "> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 card-snap-slider col-100"> <div class="slider-container js-slider-container overflow-hidden d-flex col-100"> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <div class="image-icon-sm position-absolute rounded-sm right-10 top-10"> <span class="material-icons font-20" data-icon="image"></span> </div> <a href="/quiz/where-in-america-is-that" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/92/227792-131-EB50B20E/beautiful-image-taken-arches-national-park.jpg?w=400&h=225&c=crop" alt="Beautiful Image taken at Arches National Park in Utah" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/where-in-america-is-that" class="font-weight-bold font-16 lh-sm">Where in America is That?</a> <div class="font-serif mt-10 font-14"> Crisscross the U.S. by placing these famous landmarks. </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/from-athena-to-zeus-basics-of-greek-mythology" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/22/99622-131-65926F1A/Parthenon-Athens.jpg?w=400&h=225&c=crop" alt="Parthenon, Acropolis, Athens, Greece." class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/from-athena-to-zeus-basics-of-greek-mythology" class="font-weight-bold font-16 lh-sm">From Athena to Zeus: Basics of Greek Mythology</a> <div class="font-serif mt-10 font-14"> Do you know which hero took a dip in the River Styx? Or what mysteries lurk inside the Labyrinth? </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/ultimate-animals-quiz" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/80/140480-131-28E57753/Dromedary-camels.jpg?w=400&h=225&c=crop" alt="Dromedary camels (Camelus dromedarius). Animals, mammals." class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/ultimate-animals-quiz" class="font-weight-bold font-16 lh-sm">Ultimate Animals Quiz</a> <div class="font-serif mt-10 font-14"> What is a rattlesnake’s rattle made of? What animals can go over 180 miles an hour? </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <div class="image-icon-sm position-absolute rounded-sm right-10 top-10"> <span class="material-icons font-20" data-icon="image"></span> </div> <a href="/quiz/guess-the-language" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/66/236366-131-68E4F516/Hello-in-Thai.jpg?w=400&h=225&c=crop" alt="The word "Hello" written in Thai" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/guess-the-language" class="font-weight-bold font-16 lh-sm">Guess the Language! Quiz</a> <div class="font-serif mt-10 font-14"> Can you recognize a language by its greeting? </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/best-picture-movie-quote-quiz" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/14/240414-131-1042720D/Casablanca-film.jpg?w=400&h=225&c=crop" alt="Publicity still with Humphrey Bogart and Ingrid Bergman from the motion picture film "Casablanca" (1942); directed by Michael Curtiz. (cinema, movies)" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/best-picture-movie-quote-quiz" class="font-weight-bold font-16 lh-sm">Best Picture Movie Quote Quiz</a> <div class="font-serif mt-10 font-14"> Take this quiz or you may regret it. Maybe not today, maybe not tomorrow, but soon, and for the rest of your life. </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/american-civil-rights-movement-quiz" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/13/114513-131-E18DA695/Martin-Luther-King-Jr-Malcolm-X-1964.jpg?w=400&h=225&c=crop" alt="Martin Luther King, Jr. (left of centre) and Malcolm X (right) waiting for a press conference, 1964." class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/american-civil-rights-movement-quiz" class="font-weight-bold font-16 lh-sm">American Civil Rights Movement Quiz</a> <div class="font-serif mt-10 font-14"> Test your knowledge of Americans’ tumultuous fight to end racial segregation and discrimination. </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <div class="image-icon-sm position-absolute rounded-sm right-10 top-10"> <span class="material-icons font-20" data-icon="image"></span> </div> <a href="/quiz/name-that-thing-tools" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/65/237065-131-4D50D54E/Name-that-Thing-Tools-composite-image.jpg?w=400&h=225&c=crop" alt="Name that Thing - Tools, composite image: calipers, hammer claw, pestle, trowel" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/name-that-thing-tools" class="font-weight-bold font-16 lh-sm">Name That Thing: Tools</a> <div class="font-serif mt-10 font-14"> A handy quiz to test your tool acumen. </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/the-dog-breed-quiz" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/87/232787-131-33E4C22A/retriever-dog-breeds.jpg?w=400&h=225&c=crop" alt="Various retriever dog breeds sitting in a row. L-R: curly coated retriever, golden retriever, Labrador retriever, duck tolling retriever, flat coated retriever. hunting sporting dogs" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/the-dog-breed-quiz" class="font-weight-bold font-16 lh-sm">The Dog Breed Quiz</a> <div class="font-serif mt-10 font-14"> Find out which breed can outrun a cheetah, which breed was created by monks, and much more. </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/baking-and-baked-goods" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/79/143279-131-AD0E874F/Slices-lemon-pie-meringue.jpg?w=400&h=225&c=crop" alt="Slices of lemon pie topped with meringue." class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/baking-and-baked-goods" class="font-weight-bold font-16 lh-sm">Baking and Baked Goods Quiz</a> <div class="font-serif mt-10 font-14"> You may have a sweet tooth, but how much do you know about baking and baked goods? Test your knowledge with this quiz. </div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25 quiz-card"> <div class="card text-normal col-100 "> <div class="card-media position-relative"> <a href="/quiz/first-ladies-of-the-united-states" style="--aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/89/236189-131-46FF66C0/First-Ladies-dedication-of-Ronald-Reagan-Presidential-Library-November-1991.jpg?w=400&h=225&c=crop" alt="(From left): First Ladies Barbara Bush, Nancy Reagan, Rosalynn Carter, Betty Ford, Pat Nixon, and Lady Bird Johnson at the Dedication of the Ronald Reagan Presidential Library, Simi Valley, California; November 4, 1991. (first lady)" class="col-100" /> </a> </div> <div class="col"> <div class="card-body text-hyphenate"> <a href="/quiz/first-ladies-of-the-united-states" class="font-weight-bold font-16 lh-sm">First Ladies of the United States Quiz</a> <div class="font-serif mt-10 font-14"> They have been hostesses, helpers, advisers, gatekeepers, guardians, confidantes, and sometimes formidable powers behind... </div> </div> </div> </div> </div> </div> <button disabled class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-lg btn-blue " aria-label="Previous"> <span class="material-icons md-24" data-icon="keyboard_arrow_left"></span> </button> <button disabled class="next-button js-next-button position-absolute btn btn-circle shadow btn-lg btn-blue " aria-label="Next"> <span class="material-icons md-24" data-icon="keyboard_arrow_right"></span> </button> </div> </div> </div> <div class="container qa-videos my-40"> <h2 class="mb-15 d-inline-block">Featured Videos</h2> <a href="/videos" class="font-weight-bold ml-10 font-14">See All Videos</a> <div class="grid video-player-with-playlist"> <div class="col-100 col-md-65"> <div id="vpwpl-video-player-container" class="vpwpl-video-thumbnail-container position-relative top-0"> <img loading="lazy" src="https://cdn.britannica.com/01/266301-138-6B1E5CD1/why-is-the-great-gatsby-so-memorable.jpg" alt="Leonardo DiCaprio as Jay Gatsby raises a champagne glass, with "The Great Gatsby" book cover superimposed and an arrow pointing to it." class="rounded super-video-thumbnail" /> <div class="btn btn-xl border border-white btn-circle position-absolute shadow" style="border-width: 4px; top: 50%; left:50%; transform: translate(-50%,-50%)"> <em class="material-icons text-white" data-icon="play_arrow"></em> </div> </div> <div class="vpwpl-video-title mt-10 font-weight-bold mb-10"> <em>The Great Gatsby</em>: From flop to Great American Novel </div> <div class="vpwpl-credit mb-20 font-13 text-gray-600 font-italic "> Encyclopædia Britannica, Inc. </div> </div> <ul class=" col-100 col-md-35 pl-md-30 vpwpl-playlist mt-15 mt-md-0"> <li class="vpwpl-video-item-1 vpwpl-video-item video-playing" data-assemblyid="327435"> <script type="application/json">{"image":"https://cdn.britannica.com/01/266301-138-6B1E5CD1/why-is-the-great-gatsby-so-memorable.jpg","sources":[{"file":"//content.jwplatform.com/manifests/N2BnzdEM.m3u8"}],"assetId":266301,"adfile":"//content.jwplatform.com/manifests/jcXA3d42.m3u8","title":"<em>The Great Gatsby<\/em>: From flop to Great American Novel","tracks":[{"file":"//assets-jpcust.jwpsrv.com/tracks/Khon0RJl.vtt","label":"English"}],"transcriptUrl":"/video/why-is-the-great-gatsby-so-memorable/-327435#transcript"}</script> <script data-id="video-credit" type="text/plain">Encyclopædia Britannica, Inc.</script> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/video/why-is-the-great-gatsby-so-memorable/-327435" ><em>The Great Gatsby</em>: From flop to Great American Novel</a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/video/why-is-the-great-gatsby-so-memorable/-327435"> <img loading="lazy" src="https://cdn.britannica.com/01/266301-138-6B1E5CD1/why-is-the-great-gatsby-so-memorable.jpg?w=100&h=75&c=crop" alt="Leonardo DiCaprio as Jay Gatsby raises a champagne glass, with "The Great Gatsby" book cover superimposed and an arrow pointing to it." width="100" height="75" /> <div class="btn btn-sm border border-white btn-circle position-absolute shadow" style="border-width: 3px; top: 50%; left:50%; transform: translate(-50%,-50%)"> <em class="material-icons text-white" data-icon="play_arrow"></em> </div> </a> </div> </div> </li> <li class="vpwpl-video-item-2 vpwpl-video-item " data-assemblyid="326485"> <script type="application/json">{"image":"https://cdn.britannica.com/68/265968-138-AC04E2A6/the-problem-with-invasive-species-in-the-great-lakes-and-lake-superior.jpg","sources":[{"file":"//content.jwplatform.com/manifests/BFeNaXJA.m3u8"}],"assetId":265968,"adfile":"//content.jwplatform.com/manifests/sKnJKdZA.m3u8","title":"How invasive mussels threaten the Great Lakes","tracks":[{"file":"//assets-jpcust.jwpsrv.com/tracks/BvCwVGWG.vtt","label":"English"}],"transcriptUrl":"/video/the-problem-with-invasive-species-in-the-great-lakes-and-lake-superior/-326485#transcript"}</script> <script data-id="video-credit" type="text/plain">Encyclopædia Britannica, Inc.</script> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/video/the-problem-with-invasive-species-in-the-great-lakes-and-lake-superior/-326485" >How invasive mussels threaten the Great Lakes</a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/video/the-problem-with-invasive-species-in-the-great-lakes-and-lake-superior/-326485"> <img loading="lazy" src="https://cdn.britannica.com/68/265968-138-AC04E2A6/the-problem-with-invasive-species-in-the-great-lakes-and-lake-superior.jpg?w=100&h=75&c=crop" alt="The video thumbnail image shows two hands holding zebra and quagga mussels, superimposed above a clear body of water. White question marks appear in the upper left corner." width="100" height="75" /> <div class="btn btn-sm border border-white btn-circle position-absolute shadow" style="border-width: 3px; top: 50%; left:50%; transform: translate(-50%,-50%)"> <em class="material-icons text-white" data-icon="play_arrow"></em> </div> </a> </div> </div> </li> <li class="vpwpl-video-item-3 vpwpl-video-item " data-assemblyid="324614"> <script type="application/json">{"image":"https://cdn.britannica.com/34/264634-138-26390757/how-did-cats-become-such-a-big-part-of-human-lives-video.jpg","sources":[{"file":"//content.jwplatform.com/manifests/OhH55j7l.m3u8"}],"assetId":264634,"adfile":"//content.jwplatform.com/manifests/lRS94uwC.m3u8","title":"How cats became pets","tracks":[{"file":"//assets-jpcust.jwpsrv.com/tracks/l5m6L5vw.vtt","label":"English"}],"transcriptUrl":"/video/how-did-cats-become-such-a-big-part-of-human-lives-video/-324614#transcript"}</script> <script data-id="video-credit" type="text/plain">Encyclopædia Britannica, Inc.</script> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/video/how-did-cats-become-such-a-big-part-of-human-lives-video/-324614" >How cats became pets</a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/video/how-did-cats-become-such-a-big-part-of-human-lives-video/-324614"> <img loading="lazy" src="https://cdn.britannica.com/34/264634-138-26390757/how-did-cats-become-such-a-big-part-of-human-lives-video.jpg?w=100&h=75&c=crop" alt="The video thumbnail images includes a split image of a lion and an orange cat are shown against a vintage map." width="100" height="75" /> <div class="btn btn-sm border border-white btn-circle position-absolute shadow" style="border-width: 3px; top: 50%; left:50%; transform: translate(-50%,-50%)"> <em class="material-icons text-white" data-icon="play_arrow"></em> </div> </a> </div> </div> </li> <li class="vpwpl-video-item-4 vpwpl-video-item " data-assemblyid="325677"> <script type="application/json">{"image":"https://cdn.britannica.com/71/257771-138-3E69F714/are-there-really-right-brained-and-left-brained-people.jpg","sources":[{"file":"//content.jwplatform.com/manifests/yRdwL4Tl.m3u8"}],"assetId":257771,"adfile":"//content.jwplatform.com/manifests/1lN8xmRe.m3u8","title":"Can you really be left-brained or right-brained?","tracks":[{"file":"//assets-jpcust.jwpsrv.com/tracks/qNI3ClHf.vtt","label":"English"}],"transcriptUrl":"/video/are-there-really-right-brained-and-left-brained-people/-325677#transcript"}</script> <script data-id="video-credit" type="text/plain">Encyclopædia Britannica, Inc.</script> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/video/are-there-really-right-brained-and-left-brained-people/-325677" >Can you really be left-brained or right-brained?</a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/video/are-there-really-right-brained-and-left-brained-people/-325677"> <img loading="lazy" src="https://cdn.britannica.com/71/257771-138-3E69F714/are-there-really-right-brained-and-left-brained-people.jpg?w=100&h=75&c=crop" alt="Two halves of the human brain are separated with arrows pointing to each half and a question mark in the center." width="100" height="75" /> <div class="btn btn-sm border border-white btn-circle position-absolute shadow" style="border-width: 3px; top: 50%; left:50%; transform: translate(-50%,-50%)"> <em class="material-icons text-white" data-icon="play_arrow"></em> </div> </a> </div> </div> </li> <li class="vpwpl-video-item-5 vpwpl-video-item " data-assemblyid="320861"> <script type="application/json">{"image":"https://cdn.britannica.com/09/263409-138-13478D0F/how-to-preserve-lgbtq-history-and-culture.jpg","sources":[{"file":"//content.jwplatform.com/manifests/9QFGa20s.m3u8"}],"assetId":263409,"adfile":"//content.jwplatform.com/manifests/8QzduiGm.m3u8","title":"How to preserve LGBTQ+ history in the face of hate","tracks":[{"file":"//assets-jpcust.jwpsrv.com/tracks/G7IBbEJB.vtt","label":"English"}],"transcriptUrl":"/video/how-to-preserve-lgbtq-history-and-culture/-320861#transcript"}</script> <script data-id="video-credit" type="text/plain">Encyclopædia Britannica, Inc.</script> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/video/how-to-preserve-lgbtq-history-and-culture/-320861" >How to preserve LGBTQ+ history in the face of hate</a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/video/how-to-preserve-lgbtq-history-and-culture/-320861"> <img loading="lazy" src="https://cdn.britannica.com/09/263409-138-13478D0F/how-to-preserve-lgbtq-history-and-culture.jpg?w=100&h=75&c=crop" alt="A split image showing two women from behind near a lake labeled "1969," and two women smiling and embracing labeled "2024," connected by an arrow." width="100" height="75" /> <div class="btn btn-sm border border-white btn-circle position-absolute shadow" style="border-width: 3px; top: 50%; left:50%; transform: translate(-50%,-50%)"> <em class="material-icons text-white" data-icon="play_arrow"></em> </div> </a> </div> </div> </li> <li class="vpwpl-video-item-6 vpwpl-video-item " data-assemblyid="325041"> <script type="application/json">{"image":"https://cdn.britannica.com/52/259152-138-46E57BC5/the-spitting-cobra-video.jpg","sources":[{"file":"//content.jwplatform.com/manifests/8rRuUU4C.m3u8"}],"assetId":259152,"adfile":"//content.jwplatform.com/manifests/Dk0BbGfh.m3u8","title":"Why spitting cobras don't technically spit","tracks":[{"file":"//assets-jpcust.jwpsrv.com/tracks/BjW1raFh.vtt","label":"English"}],"transcriptUrl":"/video/the-spitting-cobra-video/-325041#transcript"}</script> <script data-id="video-credit" type="text/plain">Encyclopædia Britannica, Inc.</script> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/video/the-spitting-cobra-video/-325041" >Why spitting cobras don't technically spit</a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/video/the-spitting-cobra-video/-325041"> <img loading="lazy" src="https://cdn.britannica.com/52/259152-138-46E57BC5/the-spitting-cobra-video.jpg?w=100&h=75&c=crop" alt="The video thumbnail image shows a spitting cobra shooting venom from its teeth." width="100" height="75" /> <div class="btn btn-sm border border-white btn-circle position-absolute shadow" style="border-width: 3px; top: 50%; left:50%; transform: translate(-50%,-50%)"> <em class="material-icons text-white" data-icon="play_arrow"></em> </div> </a> </div> </div> </li> </ul> </div> </div> <div class="container my-40"> <DIV class="marketing-HOMEPAGE_BOTTOM_SUBSCRIBE2 marketing-content" data-marketing-id="HOMEPAGE_BOTTOM_SUBSCRIBE2"><div class="grid pr-15 pb-15 pt-5 shadow-sm m-5" style="border:#ddd; border-width:2px; border-style:solid; background-color:#FFFFFF;"> <div class="col-sm-40 col-100 text-center"> <a href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=hp-bottom&utm_campaign=compact-evergreen"><img class="col-70 col-sm-100" src="https://cdn.britannica.com/marketing/Premium-alldevices-white-2024.jpg" style="width: 100%;"> </a> </div> <div class="col text-center text-sm-left"> <h1 class="mb-10 mt-5 mr-sm-20 font-serif"><font face="-apple-system, system-ui, Helvetica Neue, Segoe UI, Roboto, Arial, sans-serif"><span style="font-size: 14px; text-transform: capitalize;">Britannica Premium Subscription</span> </font></h1> <h1 class="mb-5 mt-10 mr-sm-20 font-serif"><span style="font-family: var(--font-family-serif); color: var(--body-color); font-size: 26px;">Unlock Exclusive Content!</span></h1> <span class="mb-0 mt-0 mr-sm-20 font-serif font-serif font-size-sm line-height-sm font-weight-base">Britannica's content is among the most trusted in the world. Subscribe to Britannica Premium and unlock our entire database of trusted content today.</span> </br> <a class="retargetA btn mt-sm-15 mt-20 mb-5 btn-orange btn-md" href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=hp-bottom&utm_campaign=compact-evergreen">Subscribe Now!</a> </div> </div></DIV></div> <div class="container explore-britannica my-40"> <h2 class="mt-20 mb-0 font-serif">Explore <span>Britannica</span></h2> <div class="grid"> <div class="col-100 col-sm-50 col-md-33"> <h3 class="font-serif link-blue-dark font-24 m-0 border-top mt-20 pt-15"> <a class="" href="History-Society">History & Society</a> </h3> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/is-body-language-universal"> <img loading="lazy" src="https://cdn.britannica.com/45/213945-131-86FBF710/Frowning-little-girl.-Angry-annoyed.jpg?w=100&h=75&c=crop" alt="Frowning little girl. Angry annoyed" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/is-body-language-universal" >Is Body Language Universal? </a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/event/2022-Russian-invasion-of-Ukraine"> <img loading="lazy" src="https://cdn.britannica.com/25/236625-050-69AADC7C/Russia-Ukraine-War-residential-building-damaged-by-a-missile-February-25-2022-in-Kyiv-Ukraine.jpg?w=100&h=75&c=crop" alt="Russia-Ukraine War" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/event/2022-Russian-invasion-of-Ukraine" >The Ongoing History of the Russia-Ukraine War</a> </div> </div> </div> <div class="col-100 col-sm-50 col-md-33"> <h3 class="font-serif link-blue-dark font-24 m-0 border-top mt-20 pt-15"> <a class="" href="Science-Tech">Science & Tech</a> </h3> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/do-lie-detectors-actually-work"> <img loading="lazy" src="https://cdn.britannica.com/58/195958-131-9F60173C/Polygraph-Lie-Detector-Machine.jpg?w=100&h=75&c=crop" alt="Polygraph Lie Detector Machine" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/do-lie-detectors-actually-work" >Do Lie Detectors Actually Work?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/science/history-of-artificial-intelligence"> <img loading="lazy" src="https://cdn.britannica.com/81/191581-050-8C0A8CD3/Alan-Turing.jpg?w=100&h=75&c=crop" alt="Alan Turing" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/science/history-of-artificial-intelligence" >History of Artificial Intelligence</a> </div> </div> </div> <div class="col-100 col-sm-50 col-md-33"> <h3 class="font-serif link-blue-dark font-24 m-0 border-top mt-20 pt-15"> <a class="" href="Biographies">Biographies</a> </h3> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/biography/Ida-B-Wells-Barnett"> <img loading="lazy" src="https://cdn.britannica.com/85/218285-050-510FA8AB/Ida-B-Wells-Barnett-circa-1893.jpg?w=100&h=75&c=crop" alt="Ida B. Wells-Barnett" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/biography/Ida-B-Wells-Barnett" >Ida B. Wells-Barnett </a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/biography/Volodymyr-Zelensky"> <img loading="lazy" src="https://cdn.britannica.com/13/270413-050-F89F0B0C/ukraine-president-volodymyr-zenesky-speaks-at-press-conference-march-15-2025.jpg?w=100&h=75&c=crop" alt="Volodymyr Zelensky" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/biography/Volodymyr-Zelensky" >Volodymyr Zelensky</a> </div> </div> </div> <div class="col-100 col-sm-50 col-md-33"> <h3 class="font-serif link-blue-dark font-24 m-0 border-top mt-20 pt-15"> <a class="" href="Animals-Nature">Animals & Nature</a> </h3> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/the-fastest-animals-on-earth"> <img loading="lazy" src="https://cdn.britannica.com/00/152300-131-FEE1926E/Cheetah-Maasai-Mara-National-Reserve-Kenya.jpg?w=100&h=75&c=crop" alt="Cheetah (Acinonyx jubatus) standing on rock, side view, Masai Mara National Reserve, Kenya" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/the-fastest-animals-on-earth" >The Fastest Animals on Earth </a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/working-like-a-dog-7-animals-with-jobs"> <img loading="lazy" src="https://cdn.britannica.com/26/187226-131-9C8C8D34/dog-package-German-Shepherd-explosives-drugs.jpg?w=100&h=75&c=crop" alt="Working German Shepherd dog sniffing a suspecting package for drugs or explosives." width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/working-like-a-dog-7-animals-with-jobs" >Working Like a Dog: 7 Animals with Jobs </a> </div> </div> </div> <div class="col-100 col-sm-50 col-md-33"> <h3 class="font-serif link-blue-dark font-24 m-0 border-top mt-20 pt-15"> <a class="" href="Geography-Travel">Geography & Travel</a> </h3> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/the-largest-islands-in-the-world"> <img loading="lazy" src="https://cdn.britannica.com/10/153510-131-EFC73A4D/Sisimiut-Greenland-Davis-Strait.jpg?w=100&h=75&c=crop" alt="Town of Sisimiut located on the coast of the Davis Strait on Kangerluarsunnguaq Bay, Greenland" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/the-largest-islands-in-the-world" >The Largest Islands in the World </a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/which-waters-do-you-pass-through-when-you-sail-the-seven-seas"> <img loading="lazy" src="https://cdn.britannica.com/97/196697-131-0155C802/Sailboat-landscape.jpg?w=100&h=75&c=crop" alt="Sailboat against a beautiful landscape" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/which-waters-do-you-pass-through-when-you-sail-the-seven-seas" >Which Waters Do You Pass Through When You “Sail the Seven Seas”?</a> </div> </div> </div> <div class="col-100 col-sm-50 col-md-33"> <h3 class="font-serif link-blue-dark font-24 m-0 border-top mt-20 pt-15"> <a class="" href="Arts-Culture">Arts & Culture</a> </h3> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/10-famous-clowns-from-comical-to-creepy"> <img loading="lazy" src="https://cdn.britannica.com/98/196498-131-14B78278/Pennywise-Bill-Skarsgard-film-adaptation-novel-Stephen.jpg?w=100&h=75&c=crop" alt="Still from the 2017 movie IT, Bill Skarsgard plays Pennywise the clown. Directed by Andy Muschietti" width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/10-famous-clowns-from-comical-to-creepy" >10 Famous Clowns: From Comical to Creepy</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mt-20 card-sm" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/cervantes-after-400-years"> <img loading="lazy" src="https://cdn.britannica.com/08/115108-131-4E70053F/Miguel-de-Cervantes-1590.jpg?w=100&h=75&c=crop" alt="Spanish poet and novelist Miguel de Cervantes Saavedra (1547 - 1616), the author of 'Don Quixote de la Mancha', ca. 1590. An artist's impression since there are no contemporary likenesses of Cervantes." width="100" height="75" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/cervantes-after-400-years" >The Afterlife of Miguel de Cervantes</a> </div> </div> </div> </div> </div> <div class="container calcularors mt-60 mb-40"> <h2 class="mb-20 font-serif link-blue-dark"><a href="/calculators">Calculators</a></h2> <div class="m-n10 "> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 card-snap-slider col-100"> <div class="slider-container js-slider-container overflow-hidden d-flex col-100"> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25"> <div class="card col-100"> <div class="col"> <div class="card-body text-hyphenate"> <a href="/calculators/mortgage-calculator" class="font-weight-bold font-16 lh-sm">Mortgage Payment Calculator</a> <div class="font-serif mt-10 font-14"> Estimate your monthly mortgage payments with our free mortgage calculator. Account for interest rates, compound frequency and pay back schedule.</div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25"> <div class="card col-100"> <div class="col"> <div class="card-body text-hyphenate"> <a href="/calculators/compound-interest-calculator" class="font-weight-bold font-16 lh-sm">Compound Interest Calculator</a> <div class="font-serif mt-10 font-14"> Compounding means getting returns on your previous returns plus your initial investment. Learn how to grow your savings with our compound interest calculator.</div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25"> <div class="card col-100"> <div class="col"> <div class="card-body text-hyphenate"> <a href="/calculators/percent-increase-calculator" class="font-weight-bold font-16 lh-sm">Percentage Increase Calculator</a> <div class="font-serif mt-10 font-14"> Calculate the increase from one value to another with our free percentage increase calculator. Evaluate population growth, inflation, stock values and more.</div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25"> <div class="card col-100"> <div class="col"> <div class="card-body text-hyphenate"> <a href="/calculators/retirement-calculator" class="font-weight-bold font-16 lh-sm">Retirement Income Calculator</a> <div class="font-serif mt-10 font-14"> Are you on track for retirement? Use our free retirement calculator to help determine how much you'll need to save each year to retire at your desired age.</div> </div> </div> </div> </div> <div class="p-10 d-inline-flex col-100 col-sm-33 col-md-25"> <div class="card col-100"> <div class="col"> <div class="card-body text-hyphenate"> <a href="/calculators/tvm-calculator" class="font-weight-bold font-16 lh-sm">Time Value of Money (TVM) Calculator</a> <div class="font-serif mt-10 font-14"> The time value of money (TVM) principle asserts that the same amount of money is worth more now than in the future. Use our TVM calculator to estimate future value, present value & more.</div> </div> </div> </div> </div> </div> <button disabled class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-lg btn-blue " aria-label="Previous"> <span class="material-icons md-24" data-icon="keyboard_arrow_left"></span> </button> <button disabled class="next-button js-next-button position-absolute btn btn-circle shadow btn-lg btn-blue " aria-label="Next"> <span class="material-icons md-24" data-icon="keyboard_arrow_right"></span> </button> </div> </div> </div> <div class="container my-40 qa-more"> <h2 class="mt-20 mb-15 font-weight-bold">More From Britannica</h2> <div class="grid gy-30"> <div class="col-100 col-sm-50 col-md-25"> <div class="border-orange border-top-10 p-20 shadow text-center h-100"> <a class="font-weight-bold font-18" href="/procon" target="_blank">ProCon</a> <div class="mt-10 font-serif">Award-winning ProCon promotes critical thinking, education, and informed citizenship by presenting the pro and con arguments to controversial issues in a straightforward, nonpartisan, freely accessible way.</div> </div> </div> <div class="col-100 col-sm-50 col-md-25"> <div class="border-green-dark border-top-10 p-20 shadow text-center h-100"> <a class="font-weight-bold font-18" href="/money">Britannica Money</a> <div class="mt-10 font-serif">Discover all you need to know about retirement, investing, and household finance, without the jargon or agenda. Get reliable guidance, insight, and easy-to-understand explanations, written, edited, and verified to Britannica’s exacting standards.</div> </div> </div> <div class="col-100 col-sm-50 col-md-25"> <div class="border-purple border-top-10 p-20 shadow text-center h-100"> <a class="font-weight-bold font-18" href="https://explore.britannica.com/explore/savingearth/advocacy/" target="_blank" rel="noopener">Advocacy for Animals</a> <div class="mt-10 font-serif"> Presenting <em class="font-weight-bold">Advocacy for Animals</em>, a blog focused primarily on animal rights, wildlife conservation, environmental health and safety, and the legal and cultural issues related to these topics. This blog is a source of information and a call to action. It is meant to be a provocation and a stimulus to thought regarding humanity’s relationship with nonhuman animals. </div> </div> </div> <div class="col-100 col-sm-50 col-md-25"> <div class="border-red border-top-10 p-20 shadow text-center h-100"> <a class="font-weight-bold font-18" href="https://alainelkanninterviews.com/" target="_blank" rel="noopener">Alain Elkann Interviews</a> <div class="mt-10 font-serif">Alain has been writing a weekly interview column for the Italian newspaper La Stampa since 1989. His interviews celebrate some of the best known and successful personalities of the present day.</div> </div> </div> </div> </div> </div> </div> </div> </main> <div id="md-footer"></div> <footer class="md-footer footer-wrapper hide-on-edit"> <div class="footer-bck"> <DIV class="marketing-FOOTER_NEWSLETTER marketing-content" data-marketing-id="FOOTER_NEWSLETTER"><div class="md-footer-newsletter-form pt-10 mb-30 mx-15 mx-sm-120"> <div class="font-18"> <strong>History at your fingertips –</strong> Sign up here to see what happened On This Day, every day in your inbox! </div> <div class="p-30"> <div class="newsletter-form-container"> <form class="newsletter-form" method="post" action="/newsletter-subscription/EB_ON_THIS_DAY"> <div class="form-group grid d-flex justify-content-center"> <div class="col-sm-50 col-100"> <label class="sr-only" for="enter-your-email">Enter your email</label> <input id="enter-your-email" type="email" name="email" class="form-control font-18 p-10" placeholder="Enter your email" pattern="[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,4}$" required> </div> <div class="col-sm-auto col-100 mt-5 mt-sm-0"> <button type="submit" class="btn btn-outline-white" style="width: 100%; height:100%;">Subscribe</button> </div> </div> <div class="text-white pt-30 text-opacity"> By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica.<br> Click here to view our <a class="link-white text-decoration-underline" href="https://corporate.britannica.com/privacy-policy" target="_blank" rel="noopener nofollow">Privacy Notice</a>. Easy unsubscribe links are provided in every email. </div> <input type="hidden" name="source" value="Footer" /><input type="hidden" name="campaign" value="Mendel" /><input type="hidden" name="medium" value="Box" /></form> <div class="md-subscribed hidden text-white"> <div class="my-10">Thank you for subscribing!</div> <div>Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox.</div> </div> </div> </div> </div></DIV><div class="footer container"> <div class="footer-links grid text-left"> <div class="col-100 col-sm-33 col-md-25"> <div class="collapse"> <button class="btn btn-link link-white text-uppercase font-weight-bold collapse__toggle"> Our Sites <em class="material-icons " data-icon="keyboard_arrow_down"></em> </button> <ul class="list-unstyled collapse__body"> <li><a class="link-white" href="https://kids.britannica.com/" rel="noopener" target="_blank">Britannica Kids</a></li> <li><a class="link-white" href="https://www.merriam-webster.com" rel="noopener" target="_blank">Merriam-Webster</a></li> <li><a class="link-white" href="https://britannicalearn.com/" rel="noopener" target="_blank">School & Library</a></li> <li><a class="link-white" href="https://melingo.com/" rel="noopener" target="_blank">Melingo</a></li> <li><a class="link-white" href="https://books.britannica.com/" rel="noopener" target="_blank">Britannica Books</a></li> <li><a class="link-white" href="https://escola.britannica.com.br/" rel="noopener" target="_blank">Escola</a></li> <li><a class="link-white" href="https://arabic.britannicaenglish.com/en/" rel="noopener" target="_blank">Britannica English-Arabic</a></li> <li><a class="link-white" href="https://www.nglish.com/spanish/en/" rel="noopener" target="_blank">Nglish Sp-En Translation</a></li> <li><a class="link-white" href="https://britannica.threadless.com/?utm_source=ebsite&utm_medium=footer&utm_campaign=evergreen" rel="noopener" target="_blank">Britannica Merch</a></li> </ul> </div> </div> <div class="col-100 col-sm-33 col-md-25"> <div class="collapse"> <button class="btn btn-link link-white text-uppercase font-weight-bold collapse__toggle"> International <em class="material-icons " data-icon="keyboard_arrow_down"></em> </button> <ul class="list-unstyled collapse__body"> <li><a class="link-white" href="https://britannica.com.au/" rel="noopener" target="_blank">Australia</a></li> <li><a class="link-white" href="https://britannica.com.br/" rel="noopener" target="_blank">Brazil</a></li> <li><a class="link-white" href="https://china.eb.com/" rel="noopener" target="_blank">China</a></li> <li>India</li> <li><a class="link-white" href="https://www.britannica.co.jp/" rel="noopener" target="_blank">Japan</a></li> <li><a class="link-white" href="https://britannica.es" rel="noopener" target="_blank">Latin America</a></li> <li><a class="link-white" href="https://britannica.co.uk/" rel="noopener" target="_blank">United Kingdom</a></li> </ul> </div> </div> <div class="col-100 col-sm-33 col-md-25"> <div class="collapse"> <button class="btn btn-link link-white text-uppercase font-weight-bold collapse__toggle"> Content & Editorial <em class="material-icons " data-icon="keyboard_arrow_down"></em> </button> <ul class="list-unstyled collapse__body"> <li><a class="link-white" href="https://encyclopediaapi.com/" rel="noopener" target="_blank">Encyclopaedia Britannica's Syndication API</a></li> <li><a class="link-white" href="https://corporate.britannica.com/intl_publishing.html" rel="noopener" target="_blank">International Publishing</a></li> <li><a class="link-white" href="/sitemap" >Site Map</a></li> <li><a class="link-white" href="/new-articles">New Articles</a></li> </ul> </div> </div> <div class="col-100 col-sm-33 col-md-25"> <div class="collapse"> <button class="btn btn-link link-white text-uppercase font-weight-bold collapse__toggle"> Stay Connected <em class="material-icons " data-icon="keyboard_arrow_down"></em> </button> <ul class="list-unstyled collapse__body"> <li class="md-footer-social-links"> <div class="md-social-toolbar-circle d-flex justify-content-center grayscale colored" data-value="connect" > <a class="social-icon facebook justify-content-center d-flex align-items-center align-self-center" data-provider="facebook" href="https://www.facebook.com/BRITANNICA/" target="_blank" rel="noopener"><span>Facebook</span></a> <a class="social-icon x justify-content-center d-flex align-items-center align-self-center" data-provider="x" href="https://x.com/britannica" target="_blank" rel="noopener"><span>X</span></a> <a class="social-icon youtube justify-content-center d-flex align-items-center align-self-center" data-provider="youtube" href="https://www.youtube.com/c/encyclopaediabritannica" target="_blank" rel="noopener"><span>YouTube</span></a> <a class="social-icon instagram justify-content-center d-flex align-items-center align-self-center" data-provider="instagram" href="https://www.instagram.com/britannica/" target="_blank" rel="noopener"><span>Instagram</span></a> <a class="social-icon pinterest justify-content-center d-flex align-items-center align-self-center" data-provider="pinterest" href="https://www.pinterest.com/britannica/" target="_blank" rel="noopener"> <svg height="30" width="30" viewBox="0 0 24 24" aria-hidden="true" aria-label="" role="img"><path d="M0 12c0 5.123 3.211 9.497 7.73 11.218-.11-.937-.227-2.482.025-3.566.217-.932 1.401-5.938 1.401-5.938s-.357-.715-.357-1.774c0-1.66.962-2.9 2.161-2.9 1.02 0 1.512.765 1.512 1.682 0 1.025-.653 2.557-.99 3.978-.281 1.189.597 2.159 1.769 2.159 2.123 0 3.756-2.239 3.756-5.471 0-2.861-2.056-4.86-4.991-4.86-3.398 0-5.393 2.549-5.393 5.184 0 1.027.395 2.127.889 2.726a.36.36 0 0 1 .083.343c-.091.378-.293 1.189-.332 1.355-.053.218-.173.265-.4.159-1.492-.694-2.424-2.875-2.424-4.627 0-3.769 2.737-7.229 7.892-7.229 4.144 0 7.365 2.953 7.365 6.899 0 4.117-2.595 7.431-6.199 7.431-1.211 0-2.348-.63-2.738-1.373 0 0-.599 2.282-.744 2.84-.282 1.084-1.064 2.456-1.549 3.235C9.584 23.815 10.77 24 12 24c6.627 0 12-5.373 12-12S18.627 0 12 0 0 5.373 0 12"></path></svg> </a> </div> </li> </ul> </div> </div> </div> </div> <div class="container"> <ul class="list-unstyled legal-links"> <li><a href="https://corporate.britannica.com" rel="noopener" target="_blank">About Us & Legal Info</a></li> <li><a href="https://corporate.britannica.com/contact/" target="_blank" rel="noopener nofollow">Contact Us</a></li> <li><a href="https://corporate.britannica.com/privacy-policy" target="_blank" rel="noopener nofollow">Privacy Policy</a></li> <li><a href="https://corporate.britannica.com/termsofuse.html" target="_blank" rel="noopener nofollow">Terms of Use</a></li> <li><a href="https://corporate.britannica.com/equalemployment" target="_blank" rel="noopener nofollow">Equal Opportunity</a></li> </ul> <div class="mt-20">©2025 Encyclopædia Britannica, Inc.</div> </div> </div> </footer> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Home","templateName":null,"pageNumber":1,"pagesTotal":1,"pageId":null,"pageLength":null,"initialLoad":true,"lastPageOfScroll":true} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-134/js/libs/jquery-3.5.0.min.js?v=3.134.26"></script> <script type="application/ld+json"> { "@context": "https://schema.org", "@type": "WebSite", "url": "https://www.britannica.com", "potentialAction": { "@type": "SearchAction", "target": "https://www.britannica.com/search?query={search_term}", "query-input": "required name=search_term" } } </script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-134/dist/home-page.js?v=3.134.26' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"A","adLeg":"A","userType":"ANONYMOUS","pageType":"Home","pageSubtype":null,"articleTemplateType":null,"gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false,"hasAiTopQuestions":false,"hasSimplifyButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

CINXE.COM

Encyclopedia Britannica | Britannica