Revision 1125193 of JavaScript

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<p class="summary"><strong>JavaScript</strong> (<strong>JS</strong>) is een lichtgewicht, geïnterpreteerde programmeertaal met <a href="https://en.wikipedia.org/wiki/First-class_functions">eersteklas functies</a>. Al is het het beste bekend als de scripttaal voor web pagina's, wordt het ook door <a class="external" href="https://en.wikipedia.org/wiki/JavaScript#Uses_outside_web_pages">vele niet-browser omgevingen</a> gebruikt, zoals <a class="external" href="https://nodejs.org/">node.js</a> en <a href="https://couchdb.apache.org/">Apache CouchDB</a>. JS is een <a class="mw-redirect" href="https://en.wikipedia.org/wiki/Prototype-based_programming" title="Prototype-based programming">prototype-gebaseed</a>, multi-paradigma, dynamische scripttaal, welke object-georienteerde, imperatieve, en functionele programmeerstijlen ondersteunt. Lees meer <a href="/en-US/docs/Web/JavaScript/About_JavaScript">over JavaScript</a>.</p>

<p>Deze sectie van de site is toegewijd aan de JavaScript taal zelf, en niet de delen die specifiek zijn voor Web paginas of andere omgevingen. Voor informatie over {{Glossary("API","APIs")}} die specifiek zijn voor Web paginas, kijk alsjeblieft op <a href="/en-US/docs/Web/API">Web APIs</a> en <a href="/en-US/docs/Glossary/DOM">DOM</a>.</p>

<p>The standard for JavaScript is <a href="/en-US/docs/Web/JavaScript/Language_Resources">ECMAScript</a>. As of 2012, all <a href="https://kangax.github.io/compat-table/es5/">modern browsers</a> fully support ECMAScript 5.1. Older browsers support at least ECMAScript 3. On June 17, 2015, <a href="https://www.ecma-international.org">ECMA International</a> published the sixth major version of ECMAScript, which is officially called ECMAScript 2015, and is more commonly referred to as ECMAScript 6 or ES6. The documentation presented covers ECMAScript 2015 and some of the announced features in the next version of ECMAScript (ES2016).</p>

<p>Do not confuse JavaScript with the <a href="https://en.wikipedia.org/wiki/Java_(programming_language)">Java programming language</a>. Both "Java" and "JavaScript" are trademarks or registered trademarks of Oracle in the U.S. and other countries. However, the two programming languages have very different syntax, semantics, and uses.</p>

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<h2 id="Tutorials">Tutorials</h2>

<p>Learn how to program in JavaScript with guides and tutorials.</p>

<h3 id="Introductory">Introductory</h3>

<dl>
 <dt><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide">JavaScript Guide</a></dt>
 <dd>If you are new to JavaScript, this guide will walk you through the language.</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/JavaScript_technologies_overview">JavaScript technologies overview</a></dt>
 <dd>Introduction to the web browser JavaScript landscape.</dd>
 <dt><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Introduction_to_Object-Oriented_JavaScript">Introduction to Object Oriented JavaScript</a></dt>
 <dd>Introduction to the concepts of object oriented programming in JavaScript.</dd>
</dl>

<h3 id="Intermediate">Intermediate</h3>

<dl>
 <dt><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/A_re-introduction_to_JavaScript">A re-introduction to JavaScript</a></dt>
 <dd>An overview for those who <em>think</em> they know about JavaScript.</dd>
</dl>

<dl>
 <dt><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures">JavaScript data structures</a></dt>
 <dd>Overview of available data structures in JavaScript.</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/Equality_comparisons_and_sameness">Equality comparisons and sameness</a></dt>
 <dd>JavaScript provides three different value-comparison operations: strict equality using <code>===</code>, loose equality using <code>==</code>, and the {{jsxref("Global_Objects/Object/is", "Object.is()")}} method.</dd>
</dl>

<h3 id="Advanced">Advanced</h3>

<dl>
 <dt><a href="/en-US/docs/Web/JavaScript/Inheritance_and_the_prototype_chain">Inheritance and the prototype chain</a></dt>
 <dd>Explanation of the widely misunderstood and under-estimated prototype-based inheritance.</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/Reference/Strict_mode">Strict mode</a></dt>
 <dd>A restricted variant of JavaScript, for faster performance and easier debugging.</dd>
 <dt><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Typed_arrays">JavaScript typed arrays</a></dt>
 <dd>JavaScript typed arrays provide a mechanism for accessing raw binary data.</dd>
 <dt><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Memory_Management">Memory Management</a></dt>
 <dd>Memory life cycle and garbage collection in JavaScript.</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/EventLoop">Concurrency model and Event Loop</a></dt>
 <dd>JavaScript has a concurrency model based on an "event loop".</dd>
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<h2 id="Reference">Reference</h2>

<p>Browse the complete <a href="/en-US/docs/Web/JavaScript/Reference">JavaScript reference</a> documentation.</p>

<dl>
 <dt><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects">Standard objects</a></dt>
 <dd>Get to know standard built-in objects {{jsxref("Array")}}, {{jsxref("Boolean")}}, {{jsxref("Date")}}, {{jsxref("Error")}}, {{jsxref("Function")}}, {{jsxref("JSON")}}, {{jsxref("Math")}}, {{jsxref("Number")}}, {{jsxref("Object")}}, {{jsxref("RegExp")}}, {{jsxref("String")}}, {{jsxref("Map")}}, {{jsxref("Set")}}, {{jsxref("WeakMap")}} , {{jsxref("WeakSet")}}, and others.</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/Reference/Operators">Expressions and operators</a></dt>
 <dd>Learn more about the behavior of JavaScript's operators {{jsxref("Operators/instanceof", "instanceof")}}, {{jsxref("Operators/typeof", "typeof")}}, {{jsxref("Operators/new", "new")}}, {{jsxref("Operators/this", "this")}}, the <a href="/en-US/docs/Web/JavaScript/Reference/Operators/Operator_Precedence">operator precedence</a>, and more.</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/Reference/Statements">Statements and declarations</a></dt>
 <dd>Learn how {{jsxref("Statements/do...while", "do-while")}}, {{jsxref("Statements/for...in", "for-in")}}, {{jsxref("Statements/for...of", "for-of")}}, {{jsxref("Statements/try...catch", "try-catch")}}, {{jsxref("Statements/let", "let")}}, {{jsxref("Statements/var", "var")}}, {{jsxref("Statements/const", "const")}}, {{jsxref("Statements/if...else", "if-else")}}, {{jsxref("Statements/switch", "switch")}}, and more JavaScript statements and keywords work.</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/Reference/Functions">Functions</a></dt>
 <dd>Learn how to work with JavaScript's functions to develop your applications.</dd>
</dl>

<h2 id="Tools_resources">Tools &amp; resources</h2>

<p>Helpful tools for writing and debugging your <strong>JavaScript </strong>code.</p>

<dl>
 <dt><a href="/en-US/docs/Tools">Firefox Developer Tools</a></dt>
 <dd><a href="/en-US/docs/Tools/Scratchpad">Scratchpad</a>, <a href="/en-US/docs/Tools/Web_Console">Web Console</a>, <a href="/en-US/docs/Tools/Profiler">JavaScript Profiler</a>, <a href="/en-US/docs/Tools/Debugger">Debugger</a>, and more.</dd>
 <dt><a class="external" href="https://www.getfirebug.com/">Firebug</a></dt>
 <dd>Edit, debug, and monitor CSS, HTML, and JavaScript live in any web page.</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/Shells">JavaScript Shells</a></dt>
 <dd>A JavaScript shell allows you to quickly test snippets of JavaScript code.</dd>
 <dt><a href="https://togetherjs.com/">TogetherJS</a></dt>
 <dd>Collaboration made easy.</dd>
 <dt><a href="https://stackoverflow.com/questions/tagged/javascript">Stack Overflow</a></dt>
 <dd>Stack Overflow questions tagged with "JavaScript".</dd>
 <dt><a href="/en-US/docs/Web/JavaScript/New_in_JavaScript">JavaScript versions and release notes</a></dt>
 <dd>Browse JavaScript's feature history and implementation status.</dd>
 <dt><a href="https://jsfiddle.net/">JSFiddle</a></dt>
 <dd>Edit JavaScript, CSS, HTML and get live results. Use external resources and collaborate with your team online.</dd>
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