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It provides developers with standard commands for performing common operations so they do not have to write the code from scratch.","alternateName":"Application Program Interface","url":"https://techterms.com/definition/api"} </script> </head> <body> <div id="full"> <header id="siteheader"> <div class="content"> <a href="#main" class="visuallyhidden">Skip to main content</a> <a href="/" class="logo"><img src="/svg/logo.svg" width="212" height="24" alt="TechTerms.com"></a> <div class="siteheader-middle"> <div class="searchwrapper collapsed"> <form id="search" class="search" action="/search" method="post"> <div class='autocomplete' role='combobox' aria-expanded='false' aria-owns='autocomplete-results'> <input type="text" id="term" name="term" placeholder="Search (e.g. api, ASP, PHP, C#)" aria-label="Search (e.g. psd, docx, exe, jpg, zip)" autocomplete="off" class='autocomplete-input term' aria-autocomplete='both' aria-controls='autocomplete-results'> <button id="searchsubmit" class="searchsubmit"></button> </div> <ul id='autocomplete-results' class='autocomplete-results hidden' aria-label='Search'> </ul> </form> </div> <a href="/random" class="headerbutton random" id="random"><img src="/svg/random.svg" alt="random" width="16" height="16"></a> <button id="searchtoggle"><img src="/svg/search-white.svg" alt="search" width="18" height="18"></button> </div> <div class="siteheader-right"> <button id="menuopen"><img src="/svg/menu.svg" alt="open menu" width="18" height="16"></button> <nav id="sitemenu" class="collapsed"> <button id="menuclose"><img src="/svg/close.svg" alt="close menu" width="14" height="14"></button> <ul> <li><a href="/browse/">Terms</a></li> <li><a href="/quiz/">Quizzes</a></li> <li><a href="/help/">Help Center</a></li> <li class="mobile"><a href="/random">Random Term</a></li> <li class="settings"><button id="settings"><img src="/svg/settings.svg" alt="settings" width="22" height="22"></button> <div class="settingsmenu"> <fieldset> <legend>Theme</legend> <input id="theme-default" value="default" type="radio" name="theme" checked> <label for="theme-default">Light</label> <input id="theme-dark" value="dark" type="radio" name="theme" > <label for="theme-dark">Dark</label> <input id="theme-hc" value="hc" type="radio" name="theme" > <label for="theme-hc">High Contrast</label> </fieldset> <div class="fontsizewrapper"><label for="fontsize">Font Size<input type="range" id="fontsize" name="fontsize" min="14" max="26" step="2" value="20"></label><span class="currentsize">20</span></div> <button id="resetsettings">Reset</button> </div> </li> </ul> </nav> </div> </div> </header> <main> <div class="adTopLB"> <div id='div-gpt-ad-1589388248615-0'> </div> </div> <div id="main" class="def"> <div id="left"> <div class="card hasheader"> <div class="cardheader"> <div class="breadcrumbs"><a href="/">Home</a><svg viewBox="0 0 9 14" xmlns="http://www.w3.org/2000/svg"><path d="m0 14 9-7-9-7z"/></svg><a href="/category/software">Software Terms</a><svg viewBox="0 0 9 14" xmlns="http://www.w3.org/2000/svg"><path d="m0 14 9-7-9-7z"/></svg>API Definition</div> </div> <article> <h1>API</h1> <div class="adDefRect"> <div id='div-gpt-ad-1589302365809-0'> </div> </div> <p>Stands for "Application Programming Interface." An API is a set of commands, <a href="/definition/function">functions</a>, <a href="/definition/protocol">protocols</a>, and objects that programmers can use to create <a href="/definition/software">software</a> or interact with an external system. It provides <a href="/definition/developer">developers</a> with standard commands for performing common operations so they do not have to write the code from scratch.</p> <p>APIs are available for both desktop and mobile <a href="/definition/operating_system">operating systems</a>. The <a href="/definition/windows">Windows</a> API, for example, provides developers with <a href="/definition/user_interface">user interface</a> controls and elements, such as windows, scroll bars, and <a href="/definition/dialog_box">dialog boxes</a>. It also provides commands for accessing the <a href="/definition/file_system">file system</a> and performing file operations, such as creating and deleting files. Additionally, the Windows API includes <a href="/definition/network">networking</a> commands that can be used to send and receive data over a local network or the Internet.</p> <p>Mobile APIs, such as the <a href="/definition/ios">iOS</a> API, provide commands for detecting <a href="/definition/touchscreen">touchscreen</a> input, such as tapping, <a href="/definition/swipe">swiping</a>, and rotating. It also includes common user interface elements, such as a pop-up keyboard, a search bar, and a tab bar, which provides navigation buttons the bottom of the screen. The iOS API also includes predefined functions for interacting with an iOS device's hardware, such as the camera, microphone, or speakers.</p> <p>Operating system APIs are typically integrated into the <a href="/definition/sdk">software development kit</a> for the corresponding program. For example, Apple's Xcode <a href="/definition/ide">IDE</a> allows developers to drag and drop elements into an application's interface. It also provides a list of available functions and includes <a href="/definition/syntax">syntax</a> highlighting for known elements and commands.</p> <p>While operating system APIs have a robust set of features, other types of APIs are much more basic. For example, a <a href="/definition/website">website</a> may provide an API for web developers that allows them to access specific information from the site. A website API may be as simple as a set of <a href="/definition/xml">XML</a> elements with a few basic commands for retrieving the information. </p> <div class="adBotLB"> <div id='div-gpt-ad-1589236206757-0'> </div> </div> <div class="cardfooter"> <div class="upDate"><div class="author">Updated <span class="pdate">June 20, 2016</span> by <a href="/authors/per_christensson">Per C.</a></div></div><div id="citations"> <div class="tabs"> <div role="tablist" aria-label="citations"> <button role="tab" aria-selected="false" aria-controls="apa" tabindex="-1">APA</button> <button role="tab" aria-selected="false" aria-controls="mla" tabindex="-1">MLA</button> <button role="tab" aria-selected="false" aria-controls="chicago" tabindex="-1">Chicago</button> <button role="tab" aria-selected="false" aria-controls="html" tabindex="-1">HTML</button> <button role="tab" aria-selected="false" aria-controls="link" tabindex="-1">Link</button> </div> <div class="citationwrap"> <div id="apa" role="tabpanel" class="citation" hidden> </div> <div id="mla" role="tabpanel" class="citation" hidden> </div> <div id="chicago" role="tabpanel" class="citation" hidden> </div> <div id="html" role="tabpanel" class="citation" hidden> </div> <div id="link" role="tabpanel" class="citation" hidden> <div>https://techterms.com/definition/api</div> </div> <button id="citecopy"><span class="visuallyhidden">Copy</span><svg enable-background="new 0 0 488.3 488.3" viewBox="-7.5 -7.5 495.8 503.3" xmlns="http://www.w3.org/2000/svg"><path d="m314.25 85.4h-227c-21.3 0-38.6 17.3-38.6 38.6v325.7c0 21.3 17.3 38.6 38.6 38.6h227c21.3 0 38.6-17.3 38.6-38.6v-325.7c-.1-21.3-17.4-38.6-38.6-38.6zm11.5 364.2c0 6.4-5.2 11.6-11.6 11.6h-227c-6.4 0-11.6-5.2-11.6-11.6v-325.6c0-6.4 5.2-11.6 11.6-11.6h227c6.4 0 11.6 5.2 11.6 11.6z" stroke-width="15"/><path d="m401.05 0h-227c-21.3 0-38.6 17.3-38.6 38.6 0 7.5 6 13.5 13.5 13.5s13.5-6 13.5-13.5c0-6.4 5.2-11.6 11.6-11.6h227c6.4 0 11.6 5.2 11.6 11.6v325.7c0 6.4-5.2 11.6-11.6 11.6-7.5 0-13.5 6-13.5 13.5s6 13.5 13.5 13.5c21.3 0 38.6-17.3 38.6-38.6v-325.7c0-21.3-17.3-38.6-38.6-38.6z" stroke-width="15"/></svg></button> </div> </div> </div> </div> </article> </div> <div id="defquiz" class="card"> <h2 class="heading logoheading"><img src="/img/main/quiz.png" alt="quiz" style="width:45px">Test Your Knowledge</h2> <div class="quizBox"> <div class="quizBody"> <p class="quizQuestion">Which of the following apps uses augmented reality?</p> <div class="quizTable"> <div id="ansButtonA" class="answerButton activeButton" data-answer="Anum" data-date="2024-10-01"><span class="ansLetter">A</span> <div class="answerCell"><span id="answerA" class="quizAnswer">DuoLingo</span> <div class="answerBar"> <div id="quizBarA" class="quizBar"></div><span id="quizPercA" class="quizperc">0%</span> </div> </div> </div> <div id="ansButtonB" class="answerButton activeButton" data-answer="Bnum" data-date="2024-10-01"><span class="ansLetter">B</span> <div class="answerCell"><span id="answerB" 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href="/definition/developer">Developer</a></li> </ol> <ol start="5"><li><a href="/definition/operating_system">Operating System</a></li> <li><a href="/definition/web_application">Web Application</a></li> <li><a href="/definition/function">Function</a></li> <li><a href="/definition/protocol">Protocol</a></li> </ol> </div> </div> <div class="adRightSky"> <div id='div-gpt-ad-1589233879778-0'> </div> </div> </div> <div class="techterms card"> <h2 class="heading">The Tech Terms Computer Dictionary</h2> <p>The definition of API on this page is an original definition written by the <a href="/authors/">TechTerms.com team</a>. If you would like to reference this page or cite this definition, please use the green citation bar directly below the definition.</p> <p>Our goal to explain computer terminology in a way that is easy to understand. We strive for accuracy and simplicity with every definition we publish. If you have feedback about this definition or would like to suggest a new technical term, please <a href="/contact">contact us</a>.</p> <h2 class="heading">TechTerms Newsletter</h2> <p>Improve your technical knowledge with our daily or weekly newsletter! 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