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website</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Getting_started/Web_standards">Web standards</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Getting_started/Web_standards/How_the_web_works">How the web works</a></li><li><a href="/en-US/docs/Learn_web_development/Getting_started/Web_standards/The_web_standards_model">The web standards model</a></li><li><a href="/en-US/docs/Learn_web_development/Getting_started/Web_standards/How_browsers_load_websites">How browsers load websites</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Getting_started/Soft_skills">Soft skills</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Research_and_learning">Research and learning</a></li><li><a href="/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Collaboration_and_teamwork">Collaboration and teamwork</a></li><li><a href="/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Workflows_and_processes">Workflows and processes</a></li><li><a href="/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Job_interviews">Succeeding in job interviews</a></li></ol></details></li><li class="section"><a href="/en-US/docs/Learn_web_development/Core">Core modules</a></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Core/Structuring_content">Structuring content with HTML</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Basic_HTML_syntax">Basic HTML syntax</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Webpage_metadata">What's in the head? Webpage metadata</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs">Headings and paragraphs in HTML</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance">Emphasis and importance</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Lists">Lists</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_documents">Structuring documents</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features">Advanced text features</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Creating_links">Creating links</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter">Challenge: Marking up a letter</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content">Challenge: Structuring a page of content</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_images">HTML images</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio">HTML video and audio</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Mozilla_splash_page">Challenge: Mozilla splash page</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics">HTML table basics</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Table_accessibility">HTML table accessibility</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Planet_data_table">Challenge: Structuring a planet data table</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_forms">Forms and buttons in HTML</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML">Debugging HTML</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Core/Styling_basics">CSS styling basics</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/What_is_CSS">What is CSS?</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Getting_started">Getting started with CSS</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Styling_a_bio_page">Challenge: Styling a biography page</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Basic_selectors">Basic CSS selectors</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Attribute_selectors">Attribute selectors</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Pseudo_classes_and_elements">Pseudo-classes and pseudo-elements</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Combinators">Combinators</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Box_model">The box model</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Handling_conflicts">Handling conflicts</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Values_and_units">CSS values and units</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Sizing">Sizing items in CSS</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Backgrounds_and_borders">Backgrounds and borders</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Overflow">Overflowing content</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Images_media_forms">Images, media, and form elements</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Tables">Styling tables</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Debugging_CSS">Debugging CSS</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Fundamental_CSS_comprehension">Challenge: Fundamental CSS comprehension</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Fancy_letterheaded_paper">Challenge: Creating fancy letterheaded paper</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Styling_basics/Cool-looking_box">Challenge: A cool-looking box</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Core/Text_styling">CSS text styling</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Core/Text_styling/Fundamentals">Fundamental text and font styling</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Text_styling/Styling_lists">Styling lists</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Text_styling/Styling_links">Styling links</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Text_styling/Web_fonts">Web fonts</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Text_styling/Typesetting_a_homepage">Challenge: Typesetting a community school homepage</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Core/CSS_layout">CSS layout</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Introduction">Introduction to CSS layout</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Floats">Floats</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Positioning">Positioning</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Flexbox">Flexbox</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Grids">CSS grid layout</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Responsive_Design">Responsive design</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Media_queries">Media query fundamentals</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Fundamental_Layout_Comprehension">Challenge: Fundamental layout comprehension</a></li></ol></details></li><li class="toggle"><details open=""><summary><em><a href="/en-US/docs/Learn_web_development/Core/Scripting" aria-current="page">Dynamic scripting with JavaScript</a></em></summary><ol><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript">What is JavaScript?</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/A_first_splash">A first splash into JavaScript</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/What_went_wrong">What went wrong? Troubleshooting JavaScript</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Variables">Storing the information you need — Variables</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Math">Basic math in JavaScript — numbers and operators</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Strings">Handling text — strings in JavaScript</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Useful_string_methods">Useful string methods</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Arrays">Arrays</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Silly_story_generator">Challenge: Silly story generator</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Conditionals">Making decisions in your code — conditionals</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Loops">Looping code</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Functions">Functions — reusable blocks of code</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Build_your_own_function">Build your own function</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Return_values">Function return values</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Events">Introduction to events</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Event_bubbling">Event bubbling</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Image_gallery">Challenge: Image gallery</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Object_basics">JavaScript object basics</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/DOM_scripting">DOM scripting introduction</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Network_requests">Making network requests with JavaScript</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/JSON">Working with JSON</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript">Debugging JavaScript and handling errors</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries">JavaScript frameworks and libraries</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Introduction">Introduction to client-side frameworks</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Main_features">Framework main features</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_getting_started">Getting started with React</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_todo_list_beginning">Beginning our React todo list</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_components">Componentizing our React app</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_events_state">React interactivity: Events and state</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_filtering_conditional_rendering">React interactivity: Editing, filtering, conditional rendering</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_accessibility">Accessibility in React</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_resources">React resources</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Core/Accessibility">Accessibility</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/What_is_accessibility">What is accessibility?</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/Tooling">Accessibility tooling and assistive technology</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/HTML">HTML: A good basis for accessibility</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/CSS_and_JavaScript">CSS and JavaScript accessibility best practices</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/WAI-ARIA_basics">WAI-ARIA basics</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/Multimedia">Accessible multimedia</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/Mobile">Mobile accessibility</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/Accessibility_troubleshooting">Challenge: Accessibility troubleshooting</a></li></ol></details></li><li><a href="/en-US/docs/Learn_web_development/Core/Design_for_developers">Design for developers</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Version_control">Version control</a></li><li class="section"><a href="/en-US/docs/Learn_web_development/Extensions">Extension modules</a></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects">Advanced JavaScript objects</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes">Object prototypes</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object-oriented_programming">Object-oriented programming</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript">Classes in JavaScript</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_building_practice">Object building practice</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Adding_bouncing_balls_features">Challenge: Adding features to our bouncing balls demo</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_APIs">Client-side web APIs</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Introduction">Introduction to web APIs</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Video_and_audio_APIs">Video and Audio APIs</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Drawing_graphics">Drawing graphics</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Client-side_storage">Client-side storage</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Third_party_APIs">Third-party APIs</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Async_JS">Asynchronous JavaScript</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Async_JS/Introducing">Introducing asynchronous JavaScript</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Async_JS/Promises">How to use promises</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Async_JS/Implementing_a_promise-based_API">How to implement a promise-based API</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Async_JS/Introducing_workers">Introducing workers</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Async_JS/Sequencing_animations">Challenge: Sequencing animations</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Forms">Web forms</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Your_first_form">Your first form</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/How_to_structure_a_web_form">How to structure a web form</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Basic_native_form_controls">Basic native form controls</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/HTML5_input_types">The HTML5 input types</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Other_form_controls">Other form controls</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Styling_web_forms">Styling web forms</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Advanced_form_styling">Advanced form styling</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/UI_pseudo-classes">UI pseudo-classes</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Form_validation">Client-side form validation</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Sending_and_retrieving_form_data">Sending form data</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools">Understanding client-side tools</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Overview">Client-side tooling overview</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Package_management">Package management basics</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Introducing_complete_toolchain">Introducing a complete toolchain</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Deployment">Deploying our app</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Server-side">Server-side websites</a></summary><ol><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps">Server-side first steps</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Introduction">Introduction to the server side</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Client-Server_overview">Client-Server Overview</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Web_frameworks">Server-side web frameworks</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Website_security">Website security</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django">Django web framework (Python)</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Introduction">Django introduction</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/development_environment">Setting up a Django development environment</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Tutorial_local_library_website">Django Tutorial: The Local Library website</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/skeleton_website">Django Tutorial Part 2: Creating a skeleton website</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Models">Django Tutorial Part 3: Using models</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Admin_site">Django Tutorial Part 4: Django admin site</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Home_page">Django Tutorial Part 5: Creating our home page</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Generic_views">Django Tutorial Part 6: Generic list and detail views</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Sessions">Django Tutorial Part 7: Sessions framework</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Authentication">Django Tutorial Part 8: User authentication and permissions</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Forms">Django Tutorial Part 9: Working with forms</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Testing">Django Tutorial Part 10: Testing a Django web application</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Deployment">Django Tutorial Part 11: Deploying Django to production</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/web_application_security">Django web application security</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/django_assessment_blog">Assessment: DIY Django mini blog</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs">Express web framework (Node.js)</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Introduction">Express/Node introduction</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/development_environment">Setting up a Node development environment</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Tutorial_local_library_website">Express Tutorial: The Local Library website</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/skeleton_website">Express Tutorial Part 2: Creating a skeleton website</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/mongoose">Express Tutorial Part 3: Using a Database (with Mongoose)</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/routes">Express Tutorial Part 4: Routes and controllers</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Displaying_data">Express Tutorial Part 5: Displaying library data</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/forms">Express Tutorial Part 6: Working with forms</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/deployment">Express Tutorial Part 7: Deploying to production</a></li></ol></details></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Performance">Web performance</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/why_web_performance">The "why" of web performance</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/What_is_web_performance">What is web performance?</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/Perceived_performance">Perceived performance</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/Measuring_performance">Measuring performance</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/Multimedia">Multimedia: Images</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/video">Multimedia: video</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/JavaScript">JavaScript performance optimization</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/HTML">HTML performance optimization</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/CSS">CSS performance optimization</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/business_case_for_performance">The business case for web performance</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Testing">Testing</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Introduction">Introduction to cross-browser testing</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Testing_strategies">Strategies for carrying out testing</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/HTML_and_CSS">Handling common HTML and CSS problems</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Feature_detection">Implementing feature detection</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Automated_testing">Introduction to automated testing</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Your_own_automation_environment">Setting up your own test automation environment</a></li></ol></details></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Transform_animate">Transform and animate CSS</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Security_privacy">Security and privacy</a></li><li class="section">Further resources</li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Howto">How to solve common problems</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Howto/Solve_HTML_problems">Solve common HTML problems</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Solve_CSS_problems">Solve common CSS problems</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Solve_JavaScript_problems">Solve common JavaScript problems</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Web_mechanics">Web mechanics</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Tools_and_setup">Tools and setup</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Design_and_accessibility">Design and accessibility</a></li></ol></details></li><li><a href="/en-US/docs/Learn_web_development/About">About</a></li><li><a href="/en-US/docs/Learn_web_development/Educators">Resources for educators</a></li><li><a href="/en-US/docs/Learn_web_development/Changelog">Changelog</a></li></ol></div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#prerequisites">Prerequisites</a></li><li class="document-toc-item "><a class="document-toc-link" href="#tutorials_and_challenges">Tutorials and challenges</a></li><li class="document-toc-item "><a class="document-toc-link" href="#see_also">See also</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="en-US"><header><h1>Dynamic scripting with JavaScript</h1></header><div class="section-content"><ul class="prev-next"><li><a class="button secondary" href="/en-US/docs/Learn_web_development/Core"><span class="button-wrap"> Overview: Core learning modules</span></a></li><li><a class="button secondary" href="/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript"><span class="button-wrap"> Next </span></a></li></ul> <p>JavaScript is a huge topic, with so many different features, styles, and techniques to learn, and so many APIs and tools built on top of it. This module focuses mostly on the essentials of the core language, plus some key surrounding topics — learning these topics will give you a solid basis to work from.</p></div><section aria-labelledby="prerequisites"><h2 id="prerequisites"><a href="#prerequisites">Prerequisites</a></h2><div class="section-content"><p>Before starting this module, you don't need any previous JavaScript knowledge, but you should have worked through the previous modules in the course. You should at least know <a href="/en-US/docs/Learn_web_development/Core/Structuring_content">HTML</a> and the <a href="/en-US/docs/Learn_web_development/Core/Styling_basics">basic fundamentals of CSS</a>.</p> <div class="notecard note"> <p><strong>Note:</strong> If you are working on a computer/tablet/other device where you don't have the ability to create your own files, you could try out (most of) the code examples in an online coding program such as <a href="https://jsbin.com/" class="external" target="_blank">JSBin</a> or <a href="https://glitch.com/" class="external" target="_blank">Glitch</a>.</p> </div></div></section><section aria-labelledby="tutorials_and_challenges"><h2 id="tutorials_and_challenges"><a href="#tutorials_and_challenges">Tutorials and challenges</a></h2><div class="section-content"><dl> <dt id="what_is_javascript"><a href="/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript">What is JavaScript?</a></dt> <dd> <p>Welcome to the MDN beginner's JavaScript course! In this first article we will look at JavaScript from a high level, answering questions such as "what is it?", and "what is it doing?", and making sure you are comfortable with JavaScript's purpose.</p> </dd> <dt id="a_first_splash_into_javascript"><a href="/en-US/docs/Learn_web_development/Core/Scripting/A_first_splash">A first splash into JavaScript</a></dt> <dd> <p>Now you've learned something about the theory of JavaScript, and what you can do with it, we are going to give you a crash course on the basic features of JavaScript via a completely practical tutorial. Here you'll build up a simple "Guess the number" game, step by step.</p> </dd> <dt id="what_went_wrong_troubleshooting_javascript"><a href="/en-US/docs/Learn_web_development/Core/Scripting/What_went_wrong">What went wrong? Troubleshooting JavaScript</a></dt> <dd> <p>When you built up the "Guess the number" game in the previous article, you may have found that it didn't work. Never fear — this article aims to save you from tearing your hair out over such problems by providing you with some simple tips on how to find and fix errors in JavaScript programs.</p> </dd> <dt id="storing_the_information_you_need_—_variables"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Variables">Storing the information you need — Variables</a></dt> <dd> <p>After reading the last couple of articles you should now know what JavaScript is, what it can do for you, how you use it alongside other web technologies, and what its main features look like from a high level. In this article, we will get down to the real basics, looking at how to work with the most basic building blocks of JavaScript — Variables.</p> </dd> <dt id="basic_math_in_javascript_—_numbers_and_operators"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Math">Basic math in JavaScript — numbers and operators</a></dt> <dd> <p>At this point in the course, we discuss maths in JavaScript — how we can combine operators and other features to successfully manipulate numbers to do our bidding.</p> </dd> <dt id="handling_text_—_strings_in_javascript"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Strings">Handling text — strings in JavaScript</a></dt> <dd> <p>Next, we'll turn our attention to strings — this is what pieces of text are called in programming. In this article, we'll look at all the common things that you really ought to know about strings when learning JavaScript, such as creating strings, escaping quotes in strings, and joining them together.</p> </dd> <dt id="useful_string_methods"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Useful_string_methods">Useful string methods</a></dt> <dd> <p>Now we've looked at the very basics of strings, let's move up a gear and start thinking about what useful operations we can do on strings with built-in methods, such as finding the length of a text string, joining and splitting strings, substituting one character in a string for another, and more.</p> </dd> <dt id="arrays"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Arrays">Arrays</a></dt> <dd> <p>In this lesson we'll look at arrays — a neat way of storing a list of data items under a single variable name. Here we look at why this is useful, then explore how to create an array, retrieve, add, and remove items stored in an array, and more besides.</p> </dd> <dt id="challenge_silly_story_generator"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Silly_story_generator">Challenge: Silly story generator</a> <sup>Challenge</sup></dt> <dd> <p>In this challenge, you'll be tasked with taking some of the knowledge you've picked up in this module's articles and applying it to creating a fun app that generates random silly stories. Have fun!</p> </dd> <dt id="making_decisions_in_your_code_—_conditionals"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Conditionals">Making decisions in your code — conditionals</a></dt> <dd> <p>In any programming language, the code needs to make decisions and carry out actions accordingly depending on different inputs. For example, in a game, if the player's number of lives is 0, then it's game over. In a weather app, if it is being looked at in the morning, show a sunrise graphic; show stars and a moon if it is nighttime. In this article, we'll explore how so-called conditional statements work in JavaScript.</p> </dd> <dt id="looping_code"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Loops">Looping code</a></dt> <dd> <p>Programming languages are very useful for rapidly completing repetitive tasks, from multiple basic calculations to just about any other situation where you've got a lot of similar items of work to complete. Here we'll look at the loop structures available in JavaScript that handle such needs.</p> </dd> <dt id="functions_—_reusable_blocks_of_code"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Functions">Functions — reusable blocks of code</a></dt> <dd> <p>Another essential concept in coding is <strong>functions</strong>, which allow you to store a piece of code that does a single task inside a defined block, and then call that code whenever you need it using a single short command — rather than having to type out the same code multiple times. In this article we'll explore fundamental concepts behind functions such as basic syntax, how to invoke and define them, scope, and parameters.</p> </dd> <dt id="build_your_own_function"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Build_your_own_function">Build your own function</a></dt> <dd> <p>With most of the essential theory dealt with in the previous article, this article provides practical experience. Here you will get some practice building your own, custom function. Along the way, we'll also explain some useful details of dealing with functions.</p> </dd> <dt id="function_return_values"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Return_values">Function return values</a></dt> <dd> <p>There's one last essential concept about functions for us to discuss — return values. Some functions don't return a significant value, but others do. It's important to understand what their values are, how to use them in your code, and how to make functions return useful values. We'll cover all of these below.</p> </dd> <dt id="introduction_to_events"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Events">Introduction to events</a></dt> <dd> <p>In this article, we discuss some important concepts surrounding events, and look at the fundamentals of how they work in browsers.</p> </dd> <dt id="event_bubbling"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Event_bubbling">Event bubbling</a></dt> <dd> <p>This article introduces the concepts of event bubbling, event capture, and event delegation, which are all about what happens when you add a listener to an element that contains another element, and an event then happens to the contained element.</p> </dd> <dt id="challenge_image_gallery"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Image_gallery">Challenge: Image gallery</a> <sup>Challenge</sup></dt> <dd> <p>Now that we've looked at the fundamental building blocks of JavaScript, we'll test your knowledge of loops, functions, conditionals and events by getting you to build a fairly common item you'll see on a lot of websites — a JavaScript-powered image gallery.</p> </dd> <dt id="object_basics"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Object_basics">Object basics</a></dt> <dd> <p>In this article, we'll look at fundamental JavaScript object syntax, and revisit some JavaScript features that we've already seen earlier in the course, reiterating the fact that many of the features you've already dealt with are objects.</p> </dd> <dt id="dom_scripting_introduction"><a href="/en-US/docs/Learn_web_development/Core/Scripting/DOM_scripting">DOM scripting introduction</a></dt> <dd> <p>When writing web pages and apps, one of the most common things you'll want to do is change the document structure in some way. This is usually done by manipulating the Document Object Model (DOM) via a set of built-in browser APIs for controlling HTML and styling information. In this article we'll introduce you to <strong>DOM scripting</strong>.</p> </dd> <dt id="making_network_requests_with_javascript"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Network_requests">Making network requests with JavaScript</a></dt> <dd> <p>Another very common task in modern websites and applications is making network requests to retrieve individual data items from the server to update sections of a webpage without having to load an entire new page. This seemingly small detail has had a huge impact on the performance and behavior of sites, so in this article, we'll explain the concept and look at technologies that make it possible.</p> </dd> <dt id="working_with_json"><a href="/en-US/docs/Learn_web_development/Core/Scripting/JSON">Working with JSON</a></dt> <dd> <p>JavaScript Object Notation (JSON) is a standard text-based format for representing structured data based on JavaScript object syntax. It is commonly used for transmitting data in web applications (e.g., sending some data from the server to the client, so it can be displayed on a web page, or vice versa). You'll come across it quite often, so in this article, we give you all you need to work with JSON using JavaScript, including parsing JSON so you can access data within it, and creating JSON.</p> </dd> <dt id="debugging_javascript_and_handling_errors"><a href="/en-US/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript">Debugging JavaScript and handling errors</a></dt> <dd> <p>In this lesson, we will return to the subject of debugging JavaScript (which we first looked at in <a href="/en-US/docs/Learn_web_development/Core/Scripting/What_went_wrong">What went wrong?</a>). Here we will delve deeper into techniques for tracking down errors, but also look at how to code defensively and handle errors in your code, avoiding problems in the first place.</p> </dd> </dl></div></section><section aria-labelledby="see_also"><h2 id="see_also"><a href="#see_also">See also</a></h2><div class="section-content"><dl> <dt id="scrimba_learn_javascript"><a href="https://v2.scrimba.com/learn-javascript-c0v?via=mdn" class="external" target="_blank">Scrimba: Learn JavaScript</a> <sup><em>MDN learning partner</em></sup></dt> <dd> <p><a href="https://scrimba.com?via=mdn" class="external" target="_blank">Scrimba's</a> <em>Learn JavaScript</em> course teaches you JavaScript through solving 140+ interactive coding challenges, building projects including a game, a browser extension, and even a mobile app. Scrimba features fun interactive lessons taught by knowledgeable teachers.</p> </dd> <dt id="learn_javascript"><a href="https://learnjavascript.online/" class="external" target="_blank">Learn JavaScript</a></dt> <dd> <p>An excellent resource for aspiring web developers — Learn JavaScript in an interactive environment, with short lessons and interactive tests, guided by automated assessment. The first 40 lessons are free, and the complete course is available for a small one-time payment.</p> </dd> </dl> <ul class="prev-next"><li><a class="button secondary" href="/en-US/docs/Learn_web_development/Core"><span class="button-wrap"> Overview: Core learning modules</span></a></li><li><a class="button secondary" href="/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript"><span class="button-wrap"> Next </span></a></li></ul></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" height="162" viewBox="0 0 162 162" fill="none" role="none"><mask id="b" fill="#fff"><path d="M97.203 47.04c8.113-7.886 18.004-13.871 28.906-17.492a78 78 0 0 1 33.969-3.39c11.443 1.39 22.401 5.295 32.024 11.411s17.656 14.28 23.476 23.86c5.819 9.579 9.269 20.318 10.083 31.385a69.85 69.85 0 0 1-5.387 32.44c-4.358 10.272-11.115 19.443-19.747 26.801-8.632 7.359-18.908 12.709-30.034 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Content available under <a href="/en-US/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/en-US/docs/Learn_web_development/Core/Scripting","doc":{"body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<ul class=\"prev-next\"><li><a class=\"button secondary\" href=\"/en-US/docs/Learn_web_development/Core\"><span class=\"button-wrap\"> Overview: Core learning modules</span></a></li><li><a class=\"button secondary\" href=\"/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript\"><span class=\"button-wrap\"> Next </span></a></li></ul>\n<p>JavaScript is a huge topic, with so many different features, styles, and techniques to learn, and so many APIs and tools built on top of it. This module focuses mostly on the essentials of the core language, plus some key surrounding topics — learning these topics will give you a solid basis to work from.</p>"}},{"type":"prose","value":{"id":"prerequisites","title":"Prerequisites","isH3":false,"content":"<p>Before starting this module, you don't need any previous JavaScript knowledge, but you should have worked through the previous modules in the course. You should at least know <a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content\">HTML</a> and the <a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics\">basic fundamentals of CSS</a>.</p>\n<div class=\"notecard note\">\n<p><strong>Note:</strong>\nIf you are working on a computer/tablet/other device where you don't have the ability to create your own files, you could try out (most of) the code examples in an online coding program such as <a href=\"https://jsbin.com/\" class=\"external\" target=\"_blank\">JSBin</a> or <a href=\"https://glitch.com/\" class=\"external\" target=\"_blank\">Glitch</a>.</p>\n</div>"}},{"type":"prose","value":{"id":"tutorials_and_challenges","title":"Tutorials and challenges","isH3":false,"content":"<dl>\n<dt id=\"what_is_javascript\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript\">What is JavaScript?</a></dt>\n<dd>\n<p>Welcome to the MDN beginner's JavaScript course! In this first article we will look at JavaScript from a high level, answering questions such as \"what is it?\", and \"what is it doing?\", and making sure you are comfortable with JavaScript's purpose.</p>\n</dd>\n<dt id=\"a_first_splash_into_javascript\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/A_first_splash\">A first splash into JavaScript</a></dt>\n<dd>\n<p>Now you've learned something about the theory of JavaScript, and what you can do with it, we are going to give you a crash course on the basic features of JavaScript via a completely practical tutorial. Here you'll build up a simple \"Guess the number\" game, step by step.</p>\n</dd>\n<dt id=\"what_went_wrong_troubleshooting_javascript\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/What_went_wrong\">What went wrong? Troubleshooting JavaScript</a></dt>\n<dd>\n<p>When you built up the \"Guess the number\" game in the previous article, you may have found that it didn't work. Never fear — this article aims to save you from tearing your hair out over such problems by providing you with some simple tips on how to find and fix errors in JavaScript programs.</p>\n</dd>\n<dt id=\"storing_the_information_you_need_—_variables\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Variables\">Storing the information you need — Variables</a></dt>\n<dd>\n<p>After reading the last couple of articles you should now know what JavaScript is, what it can do for you, how you use it alongside other web technologies, and what its main features look like from a high level. In this article, we will get down to the real basics, looking at how to work with the most basic building blocks of JavaScript — Variables.</p>\n</dd>\n<dt id=\"basic_math_in_javascript_—_numbers_and_operators\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Math\">Basic math in JavaScript — numbers and operators</a></dt>\n<dd>\n<p>At this point in the course, we discuss maths in JavaScript — how we can combine operators and other features to successfully manipulate numbers to do our bidding.</p>\n</dd>\n<dt id=\"handling_text_—_strings_in_javascript\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Strings\">Handling text — strings in JavaScript</a></dt>\n<dd>\n<p>Next, we'll turn our attention to strings — this is what pieces of text are called in programming. In this article, we'll look at all the common things that you really ought to know about strings when learning JavaScript, such as creating strings, escaping quotes in strings, and joining them together.</p>\n</dd>\n<dt id=\"useful_string_methods\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Useful_string_methods\">Useful string methods</a></dt>\n<dd>\n<p>Now we've looked at the very basics of strings, let's move up a gear and start thinking about what useful operations we can do on strings with built-in methods, such as finding the length of a text string, joining and splitting strings, substituting one character in a string for another, and more.</p>\n</dd>\n<dt id=\"arrays\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Arrays\">Arrays</a></dt>\n<dd>\n<p>In this lesson we'll look at arrays — a neat way of storing a list of data items under a single variable name. Here we look at why this is useful, then explore how to create an array, retrieve, add, and remove items stored in an array, and more besides.</p>\n</dd>\n<dt id=\"challenge_silly_story_generator\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Silly_story_generator\">Challenge: Silly story generator</a> <sup>Challenge</sup></dt>\n<dd>\n<p>In this challenge, you'll be tasked with taking some of the knowledge you've picked up in this module's articles and applying it to creating a fun app that generates random silly stories. Have fun!</p>\n</dd>\n<dt id=\"making_decisions_in_your_code_—_conditionals\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Conditionals\">Making decisions in your code — conditionals</a></dt>\n<dd>\n<p>In any programming language, the code needs to make decisions and carry out actions accordingly depending on different inputs. For example, in a game, if the player's number of lives is 0, then it's game over. In a weather app, if it is being looked at in the morning, show a sunrise graphic; show stars and a moon if it is nighttime. In this article, we'll explore how so-called conditional statements work in JavaScript.</p>\n</dd>\n<dt id=\"looping_code\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Loops\">Looping code</a></dt>\n<dd>\n<p>Programming languages are very useful for rapidly completing repetitive tasks, from multiple basic calculations to just about any other situation where you've got a lot of similar items of work to complete. Here we'll look at the loop structures available in JavaScript that handle such needs.</p>\n</dd>\n<dt id=\"functions_—_reusable_blocks_of_code\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Functions\">Functions — reusable blocks of code</a></dt>\n<dd>\n<p>Another essential concept in coding is <strong>functions</strong>, which allow you to store a piece of code that does a single task inside a defined block, and then call that code whenever you need it using a single short command — rather than having to type out the same code multiple times. In this article we'll explore fundamental concepts behind functions such as basic syntax, how to invoke and define them, scope, and parameters.</p>\n</dd>\n<dt id=\"build_your_own_function\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Build_your_own_function\">Build your own function</a></dt>\n<dd>\n<p>With most of the essential theory dealt with in the previous article, this article provides practical experience. Here you will get some practice building your own, custom function. Along the way, we'll also explain some useful details of dealing with functions.</p>\n</dd>\n<dt id=\"function_return_values\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Return_values\">Function return values</a></dt>\n<dd>\n<p>There's one last essential concept about functions for us to discuss — return values. Some functions don't return a significant value, but others do. It's important to understand what their values are, how to use them in your code, and how to make functions return useful values. We'll cover all of these below.</p>\n</dd>\n<dt id=\"introduction_to_events\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Events\">Introduction to events</a></dt>\n<dd>\n<p>In this article, we discuss some important concepts surrounding events, and look at the fundamentals of how they work in browsers.</p>\n</dd>\n<dt id=\"event_bubbling\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Event_bubbling\">Event bubbling</a></dt>\n<dd>\n<p>This article introduces the concepts of event bubbling, event capture, and event delegation, which are all about what happens when you add a listener to an element that contains another element, and an event then happens to the contained element.</p>\n</dd>\n<dt id=\"challenge_image_gallery\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Image_gallery\">Challenge: Image gallery</a> <sup>Challenge</sup></dt>\n<dd>\n<p>Now that we've looked at the fundamental building blocks of JavaScript, we'll test your knowledge of loops, functions, conditionals and events by getting you to build a fairly common item you'll see on a lot of websites — a JavaScript-powered image gallery.</p>\n</dd>\n<dt id=\"object_basics\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Object_basics\">Object basics</a></dt>\n<dd>\n<p>In this article, we'll look at fundamental JavaScript object syntax, and revisit some JavaScript features that we've already seen earlier in the course, reiterating the fact that many of the features you've already dealt with are objects.</p>\n</dd>\n<dt id=\"dom_scripting_introduction\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/DOM_scripting\">DOM scripting introduction</a></dt>\n<dd>\n<p>When writing web pages and apps, one of the most common things you'll want to do is change the document structure in some way. This is usually done by manipulating the Document Object Model (DOM) via a set of built-in browser APIs for controlling HTML and styling information. In this article we'll introduce you to <strong>DOM scripting</strong>.</p>\n</dd>\n<dt id=\"making_network_requests_with_javascript\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Network_requests\">Making network requests with JavaScript</a></dt>\n<dd>\n<p>Another very common task in modern websites and applications is making network requests to retrieve individual data items from the server to update sections of a webpage without having to load an entire new page. This seemingly small detail has had a huge impact on the performance and behavior of sites, so in this article, we'll explain the concept and look at technologies that make it possible.</p>\n</dd>\n<dt id=\"working_with_json\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/JSON\">Working with JSON</a></dt>\n<dd>\n<p>JavaScript Object Notation (JSON) is a standard text-based format for representing structured data based on JavaScript object syntax. It is commonly used for transmitting data in web applications (e.g., sending some data from the server to the client, so it can be displayed on a web page, or vice versa). You'll come across it quite often, so in this article, we give you all you need to work with JSON using JavaScript, including parsing JSON so you can access data within it, and creating JSON.</p>\n</dd>\n<dt id=\"debugging_javascript_and_handling_errors\"><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript\">Debugging JavaScript and handling errors</a></dt>\n<dd>\n<p>In this lesson, we will return to the subject of debugging JavaScript (which we first looked at in <a href=\"/en-US/docs/Learn_web_development/Core/Scripting/What_went_wrong\">What went wrong?</a>). Here we will delve deeper into techniques for tracking down errors, but also look at how to code defensively and handle errors in your code, avoiding problems in the first place.</p>\n</dd>\n</dl>"}},{"type":"prose","value":{"id":"see_also","title":"See also","isH3":false,"content":"<dl>\n<dt id=\"scrimba_learn_javascript\"><a href=\"https://v2.scrimba.com/learn-javascript-c0v?via=mdn\" class=\"external\" target=\"_blank\">Scrimba: Learn JavaScript</a> <sup><em>MDN learning partner</em></sup></dt>\n<dd>\n<p><a href=\"https://scrimba.com?via=mdn\" class=\"external\" target=\"_blank\">Scrimba's</a> <em>Learn JavaScript</em> course teaches you JavaScript through solving 140+ interactive coding challenges, building projects including a game, a browser extension, and even a mobile app. Scrimba features fun interactive lessons taught by knowledgeable teachers.</p>\n</dd>\n<dt id=\"learn_javascript\"><a href=\"https://learnjavascript.online/\" class=\"external\" target=\"_blank\">Learn JavaScript</a></dt>\n<dd>\n<p>An excellent resource for aspiring web developers — Learn JavaScript in an interactive environment, with short lessons and interactive tests, guided by automated assessment. The first 40 lessons are free, and the complete course is available for a small one-time payment.</p>\n</dd>\n</dl>\n<ul class=\"prev-next\"><li><a class=\"button secondary\" href=\"/en-US/docs/Learn_web_development/Core\"><span class=\"button-wrap\"> Overview: Core learning modules</span></a></li><li><a class=\"button secondary\" href=\"/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript\"><span class=\"button-wrap\"> Next </span></a></li></ul>"}}],"isActive":true,"isMarkdown":true,"isTranslated":false,"locale":"en-US","mdn_url":"/en-US/docs/Learn_web_development/Core/Scripting","modified":"2025-02-07T18:42:41.000Z","native":"English (US)","noIndexing":false,"other_translations":[{"locale":"de","title":"Dynamisches Skripting mit JavaScript","native":"Deutsch"},{"locale":"es","title":"Elementos básicos de JavaScript","native":"Español"},{"locale":"fr","title":"Premiers pas en JavaScript","native":"Français"},{"locale":"ja","title":"JavaScript による動的スクリプティング","native":"日本語"},{"locale":"ko","title":"JavaScript 구성요소","native":"한국어"},{"locale":"pt-BR","title":"Primeiros passos com JavaScript","native":"Português (do Brasil)"},{"locale":"ru","title":"Структурные элементы JavaScript","native":"Русский"},{"locale":"zh-CN","title":"创建 JavaScript 代码块","native":"中文 (简体)"},{"locale":"zh-TW","title":"JavaScript building blocks","native":"正體中文 (繁體)"}],"pageTitle":"Dynamic scripting with JavaScript - Learn web development | MDN","parents":[{"uri":"/en-US/docs/Learn_web_development","title":"Learn"},{"uri":"/en-US/docs/Learn_web_development/Core","title":"Core learning modules"},{"uri":"/en-US/docs/Learn_web_development/Core/Scripting","title":"Dynamic scripting with JavaScript"}],"popularity":null,"short_title":"Dynamic scripting with JavaScript","sidebarHTML":"<ol><li class=\"section\"><a href=\"/en-US/docs/Learn_web_development/Getting_started\">Getting started modules</a></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup\">Environment setup</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Installing_software\">Installing basic software</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Browsing_the_web\">Browsing the web</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Code_editors\">Code editors</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Dealing_with_files\">Dealing with files</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Command_line\">Command line crash course</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Getting_started/Your_first_website\">Your first website</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Your_first_website/What_will_your_website_look_like\">What will your website look like?</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Creating_the_content\">HTML: Creating the content</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Styling_the_content\">CSS: Styling the content</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Adding_interactivity\">JavaScript: Adding interactivity</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Publishing_your_website\">Publishing your website</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Getting_started/Web_standards\">Web standards</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Web_standards/How_the_web_works\">How the web works</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Web_standards/The_web_standards_model\">The web standards model</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Web_standards/How_browsers_load_websites\">How browsers load websites</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills\">Soft skills</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Research_and_learning\">Research and learning</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Collaboration_and_teamwork\">Collaboration and teamwork</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Workflows_and_processes\">Workflows and processes</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Job_interviews\">Succeeding in job interviews</a></li></ol></details></li><li class=\"section\"><a href=\"/en-US/docs/Learn_web_development/Core\">Core modules</a></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content\">Structuring content with HTML</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Basic_HTML_syntax\">Basic HTML syntax</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Webpage_metadata\">What's in the head? Webpage metadata</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs\">Headings and paragraphs in HTML</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance\">Emphasis and importance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Lists\">Lists</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_documents\">Structuring documents</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features\">Advanced text features</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Creating_links\">Creating links</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter\">Challenge: Marking up a letter</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content\">Challenge: Structuring a page of content</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_images\">HTML images</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio\">HTML video and audio</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Mozilla_splash_page\">Challenge: Mozilla splash page</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics\">HTML table basics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Table_accessibility\">HTML table accessibility</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Planet_data_table\">Challenge: Structuring a planet data table</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_forms\">Forms and buttons in HTML</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML\">Debugging HTML</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics\">CSS styling basics</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/What_is_CSS\">What is CSS?</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Getting_started\">Getting started with CSS</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Styling_a_bio_page\">Challenge: Styling a biography page</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Basic_selectors\">Basic CSS selectors</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Attribute_selectors\">Attribute selectors</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Pseudo_classes_and_elements\">Pseudo-classes and pseudo-elements</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Combinators\">Combinators</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Box_model\">The box model</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Handling_conflicts\">Handling conflicts</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Values_and_units\">CSS values and units</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Sizing\">Sizing items in CSS</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Backgrounds_and_borders\">Backgrounds and borders</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Overflow\">Overflowing content</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Images_media_forms\">Images, media, and form elements</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Tables\">Styling tables</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Debugging_CSS\">Debugging CSS</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Fundamental_CSS_comprehension\">Challenge: Fundamental CSS comprehension</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Fancy_letterheaded_paper\">Challenge: Creating fancy letterheaded paper</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Cool-looking_box\">Challenge: A cool-looking box</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling\">CSS text styling</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Fundamentals\">Fundamental text and font styling</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Styling_lists\">Styling lists</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Styling_links\">Styling links</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Web_fonts\">Web fonts</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Typesetting_a_homepage\">Challenge: Typesetting a community school homepage</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout\">CSS layout</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Introduction\">Introduction to CSS layout</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Floats\">Floats</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Positioning\">Positioning</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Flexbox\">Flexbox</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Grids\">CSS grid layout</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Responsive_Design\">Responsive design</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Media_queries\">Media query fundamentals</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Fundamental_Layout_Comprehension\">Challenge: Fundamental layout comprehension</a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary><em><a href=\"/en-US/docs/Learn_web_development/Core/Scripting\" aria-current=\"page\">Dynamic scripting with JavaScript</a></em></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript\">What is JavaScript?</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/A_first_splash\">A first splash into JavaScript</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/What_went_wrong\">What went wrong? Troubleshooting JavaScript</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Variables\">Storing the information you need — Variables</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Math\">Basic math in JavaScript — numbers and operators</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Strings\">Handling text — strings in JavaScript</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Useful_string_methods\">Useful string methods</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Arrays\">Arrays</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Silly_story_generator\">Challenge: Silly story generator</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Conditionals\">Making decisions in your code — conditionals</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Loops\">Looping code</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Functions\">Functions — reusable blocks of code</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Build_your_own_function\">Build your own function</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Return_values\">Function return values</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Events\">Introduction to events</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Event_bubbling\">Event bubbling</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Image_gallery\">Challenge: Image gallery</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Object_basics\">JavaScript object basics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/DOM_scripting\">DOM scripting introduction</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Network_requests\">Making network requests with JavaScript</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/JSON\">Working with JSON</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript\">Debugging JavaScript and handling errors</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries\">JavaScript frameworks and libraries</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Introduction\">Introduction to client-side frameworks</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Main_features\">Framework main features</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_getting_started\">Getting started with React</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_todo_list_beginning\">Beginning our React todo list</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_components\">Componentizing our React app</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_events_state\">React interactivity: Events and state</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_filtering_conditional_rendering\">React interactivity: Editing, filtering, conditional rendering</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_accessibility\">Accessibility in React</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_resources\">React resources</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility\">Accessibility</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/What_is_accessibility\">What is accessibility?</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/Tooling\">Accessibility tooling and assistive technology</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/HTML\">HTML: A good basis for accessibility</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/CSS_and_JavaScript\">CSS and JavaScript accessibility best practices</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/WAI-ARIA_basics\">WAI-ARIA basics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/Multimedia\">Accessible multimedia</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/Mobile\">Mobile accessibility</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/Accessibility_troubleshooting\">Challenge: Accessibility troubleshooting</a></li></ol></details></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Design_for_developers\">Design for developers</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Version_control\">Version control</a></li><li class=\"section\"><a href=\"/en-US/docs/Learn_web_development/Extensions\">Extension modules</a></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects\">Advanced JavaScript objects</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes\">Object prototypes</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object-oriented_programming\">Object-oriented programming</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript\">Classes in JavaScript</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_building_practice\">Object building practice</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Adding_bouncing_balls_features\">Challenge: Adding features to our bouncing balls demo</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs\">Client-side web APIs</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Introduction\">Introduction to web APIs</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Video_and_audio_APIs\">Video and Audio APIs</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Drawing_graphics\">Drawing graphics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Client-side_storage\">Client-side storage</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Third_party_APIs\">Third-party APIs</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS\">Asynchronous JavaScript</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS/Introducing\">Introducing asynchronous JavaScript</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS/Promises\">How to use promises</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS/Implementing_a_promise-based_API\">How to implement a promise-based API</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS/Introducing_workers\">Introducing workers</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS/Sequencing_animations\">Challenge: Sequencing animations</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms\">Web forms</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Your_first_form\">Your first form</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/How_to_structure_a_web_form\">How to structure a web form</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Basic_native_form_controls\">Basic native form controls</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/HTML5_input_types\">The HTML5 input types</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Other_form_controls\">Other form controls</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Styling_web_forms\">Styling web forms</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Advanced_form_styling\">Advanced form styling</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/UI_pseudo-classes\">UI pseudo-classes</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Form_validation\">Client-side form validation</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Sending_and_retrieving_form_data\">Sending form data</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools\">Understanding client-side tools</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Overview\">Client-side tooling overview</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Package_management\">Package management basics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Introducing_complete_toolchain\">Introducing a complete toolchain</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Deployment\">Deploying our app</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side\">Server-side websites</a></summary><ol><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps\">Server-side first steps</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Introduction\">Introduction to the server side</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Client-Server_overview\">Client-Server Overview</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Web_frameworks\">Server-side web frameworks</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Website_security\">Website security</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django\">Django web framework (Python)</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Introduction\">Django introduction</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/development_environment\">Setting up a Django development environment</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Tutorial_local_library_website\">Django Tutorial: The Local Library website</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/skeleton_website\">Django Tutorial Part 2: Creating a skeleton website</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Models\">Django Tutorial Part 3: Using models</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Admin_site\">Django Tutorial Part 4: Django admin site</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Home_page\">Django Tutorial Part 5: Creating our home page</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Generic_views\">Django Tutorial Part 6: Generic list and detail views</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Sessions\">Django Tutorial Part 7: Sessions framework</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Authentication\">Django Tutorial Part 8: User authentication and permissions</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Forms\">Django Tutorial Part 9: Working with forms</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Testing\">Django Tutorial Part 10: Testing a Django web application</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Deployment\">Django Tutorial Part 11: Deploying Django to production</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/web_application_security\">Django web application security</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/django_assessment_blog\">Assessment: DIY Django mini blog</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs\">Express web framework (Node.js)</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Introduction\">Express/Node introduction</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/development_environment\">Setting up a Node development environment</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Tutorial_local_library_website\">Express Tutorial: The Local Library website</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/skeleton_website\">Express Tutorial Part 2: Creating a skeleton website</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/mongoose\">Express Tutorial Part 3: Using a Database (with Mongoose)</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/routes\">Express Tutorial Part 4: Routes and controllers</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Displaying_data\">Express Tutorial Part 5: Displaying library data</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/forms\">Express Tutorial Part 6: Working with forms</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/deployment\">Express Tutorial Part 7: Deploying to production</a></li></ol></details></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance\">Web performance</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/why_web_performance\">The \"why\" of web performance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/What_is_web_performance\">What is web performance?</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/Perceived_performance\">Perceived performance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/Measuring_performance\">Measuring performance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/Multimedia\">Multimedia: Images</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/video\">Multimedia: video</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/JavaScript\">JavaScript performance optimization</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/HTML\">HTML performance optimization</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/CSS\">CSS performance optimization</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/business_case_for_performance\">The business case for web performance</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing\">Testing</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Introduction\">Introduction to cross-browser testing</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Testing_strategies\">Strategies for carrying out testing</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/HTML_and_CSS\">Handling common HTML and CSS problems</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Feature_detection\">Implementing feature detection</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Automated_testing\">Introduction to automated testing</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Your_own_automation_environment\">Setting up your own test automation environment</a></li></ol></details></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Transform_animate\">Transform and animate CSS</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Security_privacy\">Security and privacy</a></li><li class=\"section\">Further resources</li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Howto\">How to solve common problems</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Howto/Solve_HTML_problems\">Solve common HTML problems</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Solve_CSS_problems\">Solve common CSS problems</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Solve_JavaScript_problems\">Solve common JavaScript problems</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Web_mechanics\">Web mechanics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Tools_and_setup\">Tools and setup</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Design_and_accessibility\">Design and accessibility</a></li></ol></details></li><li><a href=\"/en-US/docs/Learn_web_development/About\">About</a></li><li><a href=\"/en-US/docs/Learn_web_development/Educators\">Resources for educators</a></li><li><a href=\"/en-US/docs/Learn_web_development/Changelog\">Changelog</a></li></ol>","source":{"folder":"en-us/learn_web_development/core/scripting","github_url":"https://github.com/mdn/content/blob/main/files/en-us/learn_web_development/core/scripting/index.md","last_commit_url":"https://github.com/mdn/content/commit/07d0f18e4b2ad43185bcc98ce99b7080c6411b2a","filename":"index.md"},"summary":"JavaScript is a huge topic, with so many different features, styles, and techniques to learn, and so many APIs and tools built on top of it. This module focuses mostly on the essentials of the core language, plus some key surrounding topics — learning these topics will give you a solid basis to work from.","title":"Dynamic scripting with JavaScript","toc":[{"text":"Prerequisites","id":"prerequisites"},{"text":"Tutorials and challenges","id":"tutorials_and_challenges"},{"text":"See also","id":"see_also"}],"pageType":"learn-module"}}</script></body></html>