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Version control</a></li></ol></details></li><li class="toggle"><details open=""><summary>Extensions modules</summary><ol><li><a href="/en-US/curriculum/extensions/">Extensions overview</a></li><li><a href="/en-US/curriculum/extensions/transform-and-animate-css/">1. Transform & animate CSS</a></li><li><em><a href="/en-US/curriculum/extensions/custom-js-objects/" aria-current="page">2. Custom JS objects</a></em></li><li><a href="/en-US/curriculum/extensions/web-apis/">3. Web APIs</a></li><li><a href="/en-US/curriculum/extensions/performance/">4. Performance</a></li><li><a href="/en-US/curriculum/extensions/security-and-privacy/">5. Security and privacy</a></li><li><a href="/en-US/curriculum/extensions/testing/">6. Testing</a></li><li><a href="/en-US/curriculum/extensions/a-practical-understanding-of-javascript-frameworks/">7. JavaScript frameworks</a></li><li><a href="/en-US/curriculum/extensions/css-tooling/">8. CSS tooling</a></li><li><a href="/en-US/curriculum/extensions/other-tooling-types/">9. Other tooling types</a></li></ol></details></li><li class=""><a href="/en-US/curriculum/faq/">Frequently asked questions</a></li><li class=""><a href="/en-US/curriculum/resources-for-educators/">Resources for Educators</a></li></ol></aside></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav></nav></aside><section class="place side"></section></div></div><article id="content" class="curriculum-content" lang="en-US"><header><svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 60 60" role="none" class="topic-icon topic-scripting"><circle cx="30" cy="30" r="30" fill="#fff"></circle><path fill="#6A621C" d="M22.48 38.127a7.7 7.7 0 0 1-1.6-.152q-.697-.153-.697-.559 0-.09.063-.406a3.7 3.7 0 0 1 .165-.584q.114-.267.28-.267.025 0 .279.051.33.075.571.127.255.038.571.038 1.677 0 2.412-.66.75-.66.75-2.12V22.65q0-.507.9-.507h.178q.915 0 .915.507v10.715q0 2.247-1.156 3.504-1.142 1.257-3.63 1.257m11.675 0q-1.245 0-2.323-.267-1.065-.279-1.714-.66-.635-.394-.635-.71 0-.18.14-.47.153-.293.343-.521t.304-.229q.102 0 .445.204.787.406 1.561.673.775.266 1.88.266.863 0 1.535-.33.673-.33 1.041-.927a2.6 2.6 0 0 0 .381-1.396q0-.838-.457-1.384a3.15 3.15 0 0 0-1.091-.876q-.636-.33-1.854-.812-1.32-.508-2.095-.94-.762-.445-1.307-1.282-.534-.839-.534-2.222 0-1.206.623-2.158.621-.965 1.764-1.498 1.143-.534 2.628-.533.673 0 1.536.19.864.178 1.473.495.622.318.622.699 0 .165-.14.456a2.5 2.5 0 0 1-.304.508q-.178.23-.28.229-.114 0-.457-.19a7 7 0 0 0-1.13-.483q-.558-.19-1.358-.19-1.308 0-2.12.672-.8.673-.8 1.88 0 .723.355 1.193.356.47.902.749.546.28 1.523.647.064.013.292.102 1.346.52 2.197 1.015.863.482 1.46 1.397.609.914.609 2.336 0 1.332-.622 2.323-.609.99-1.752 1.523-1.13.52-2.64.521"></path></svg><h1>2. Custom JS objects</h1><p class="module-topic">Scripting</p><p class="module-group">Extensions modules</p></header><div class="section-content"><p>Having a deeper knowledge of how JavaScript objects work is useful as you build confidence with web development, start to build more complex apps, and create your own libraries.</p> <p class="curriculum-outcomes">Learning outcomes:</p> <ul> <li> <p>Object prototypes.</p> </li> <li> <p>JavaScript class syntax.</p> </li> <li> <p>Defining a constructor.</p> </li> <li> <p>Defining properties and methods.</p> </li> <li> <p>Defining static properties and methods.</p> </li> </ul> <p class="curriculum-resources">Resources:</p> <ul> <li> <p><a href="/en-US/docs/Learn/JavaScript/Objects/Basics">JavaScript object basics</a></p> </li> <li> <p><a href="/en-US/docs/Learn/JavaScript/Objects/Object_prototypes">Object prototypes</a></p> </li> <li> <p><a href="/en-US/docs/Learn/JavaScript/Objects/Object-oriented_programming">Object-oriented programming</a></p> </li> <li> <p><a href="/en-US/docs/Learn/JavaScript/Objects/Classes_in_JavaScript">Classes in JavaScript</a></p> </li> </ul></div><section class="curriculum-prev-next"><a href="/en-US/curriculum/extensions/transform-and-animate-css/" target="_self" class="button primary has-icon"><span class="button-wrap"><span class="icon icon-curriculum-prev "></span>Previous: 1. Transform & animate CSS</span></a><a href="/en-US/curriculum/extensions/web-apis/" target="_self" class="button primary has-icon"><span class="button-wrap"><span class="icon icon-curriculum-next "></span>Next: 3. Web APIs</span></a></section></article></main></div><footer id="nav-footer" class="page-footer"><div class="page-footer-grid"><div class="page-footer-logo-col"><a href="/" class="mdn-footer-logo" aria-label="MDN homepage"><svg width="48" height="17" viewBox="0 0 48 17" fill="none" xmlns="http://www.w3.org/2000/svg"><title id="mdn-footer-logo-svg">MDN logo</title><path d="M20.04 16.512H15.504V10.416C15.504 9.488 15.344 8.824 15.024 8.424C14.72 8.024 14.264 7.824 13.656 7.824C12.92 7.824 12.384 8.064 12.048 8.544C11.728 9.024 11.568 9.64 11.568 10.392V14.184H13.008V16.512H8.472V10.416C8.472 9.488 8.312 8.824 7.992 8.424C7.688 8.024 7.232 7.824 6.624 7.824C5.872 7.824 5.336 8.064 5.016 8.544C4.696 9.024 4.536 9.64 4.536 10.392V14.184H6.6V16.512H0V14.184H1.44V8.04H0.024V5.688H4.536V7.32C5.224 6.088 6.32 5.472 7.824 5.472C8.608 5.472 9.328 5.664 9.984 6.048C10.64 6.432 11.096 7.016 11.352 7.8C11.992 6.248 13.168 5.472 14.88 5.472C15.856 5.472 16.72 5.776 17.472 6.384C18.224 6.992 18.6 7.936 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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/curriculum/extensions/custom-js-objects/","doc":{"locale":"en-US","title":"2. Custom JS objects","mdn_url":"/en-US/curriculum/extensions/custom-js-objects/","native":"English (US)","body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>Having a deeper knowledge of how JavaScript objects work is useful as you build confidence with web development, start to build more complex apps, and create your own libraries.</p>\n<p class=\"curriculum-outcomes\">Learning outcomes:</p>\n<ul>\n <li>\n <p>Object prototypes.</p>\n </li>\n <li>\n <p>JavaScript class syntax.</p>\n </li>\n <li>\n <p>Defining a constructor.</p>\n </li>\n <li>\n <p>Defining properties and methods.</p>\n </li>\n <li>\n <p>Defining static properties and methods.</p>\n </li>\n</ul>\n<p class=\"curriculum-resources\">Resources:</p>\n<ul>\n <li>\n <p><a href=\"/en-US/docs/Learn/JavaScript/Objects/Basics\">JavaScript object basics</a></p>\n </li>\n <li>\n <p><a href=\"/en-US/docs/Learn/JavaScript/Objects/Object_prototypes\">Object prototypes</a></p>\n </li>\n <li>\n <p><a href=\"/en-US/docs/Learn/JavaScript/Objects/Object-oriented_programming\">Object-oriented programming</a></p>\n </li>\n <li>\n <p><a href=\"/en-US/docs/Learn/JavaScript/Objects/Classes_in_JavaScript\">Classes in JavaScript</a></p>\n </li>\n</ul>"}}],"pageTitle":"2. 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Web APIs"}},"parents":[{"uri":"/en-US/curriculum/","title":"MDN Curriculum"},{"uri":"/en-US/curriculum/extensions/","title":"Extensions modules"},{"uri":"/en-US/curriculum/extensions/custom-js-objects/","title":"2. Custom JS objects"}],"topic":"Scripting","group":"Extensions modules","template":"module","summary":"Create custom JavaScript objects to gain a deeper understanding of object-oriented programming."}}</script></body></html>