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+---
+title: 'null'
+slug: Web/JavaScript/Reference/Global_Objects/null
+translation_of: Web/JavaScript/Reference/Global_Objects/null
+---
+<div>{{jsSidebar("Objects")}}</div>
+
+<p>De waarde <code>null</code> representeert het moedwillig weglaten, of de bedoelde afwezigheid van welk object of waarde dan ook. Het is een van JavaScript's {{Glossary("Primitive", "primitive values")}}.</p>
+
+<h2 id="Syntax">Syntax</h2>
+
+<pre class="syntaxbox"><code>null </code></pre>
+
+<h2 id="Beschrijving">Beschrijving</h2>
+
+<p>De waarde <code>null</code> wordt letterlijk geschreven als <code>null</code> (het is geen idenfifier voor een eigenschap van de global object zoals  {{jsxref("Global_Objects/undefined","undefined")}} wel kan zijn). In APIs, wordt <code>null</code> vaak verkregen op plekken waar een object mag worden verwacht, maar waar tegelijk geen object relevant is . Wanneer op null of undefined wordt gecontroleerd, wees dan bewust van de  <a href="/en-US/docs/Web/JavaScript/Reference/Operators/Comparison_Operators">verschillen tussen equality (==) en identity (===) operators</a> (type-conversie wordt via de eerste bereikt).</p>
+
+<pre class="brush: js">// foo does not exist. It is not defined and has never been initialized:
+&gt; foo
+"ReferenceError: foo is not defined"
+
+// foo is known to exist now but it has no type or value:
+&gt; var foo = null; foo
+"null"
+</pre>
+
+<h3 id="Verschil_tussen_null_en_undefined">Verschil tussen <code>null</code> en <code> undefined</code></h3>
+
+<pre class="brush: js">typeof null // object (bug in ECMAScript, should be null)
+typeof undefined // undefined
+null === undefined // false
+null == undefined // true
+</pre>
+
+<h2 id="Specificaties">Specificaties</h2>
+
+<table class="standard-table">
+ <tbody>
+ <tr>
+ <th scope="col">Specificatie</th>
+ <th scope="col">Status</th>
+ <th scope="col">Commentaar</th>
+ </tr>
+ <tr>
+ <td>{{SpecName('ES1')}}</td>
+ <td>{{Spec2('ES1')}}</td>
+ <td>Initial definition.</td>
+ </tr>
+ <tr>
+ <td>{{SpecName('ES5.1', '#sec-4.3.11', 'null value')}}</td>
+ <td>{{Spec2('ES5.1')}}</td>
+ <td> </td>
+ </tr>
+ <tr>
+ <td>{{SpecName('ES6', '#sec-null-value', 'null value')}}</td>
+ <td>{{Spec2('ES6')}}</td>
+ <td> </td>
+ </tr>
+ <tr>
+ <td>{{SpecName('ESDraft', '#sec-null-value', 'null value')}}</td>
+ <td>{{Spec2('ESDraft')}}</td>
+ <td> </td>
+ </tr>
+ </tbody>
+</table>
+
+<h2 id="Browser_compatibiliteit">Browser compatibiliteit</h2>
+
+<p>{{CompatibilityTable}}</p>
+
+<div id="compat-desktop">
+<table class="compat-table">
+ <tbody>
+ <tr>
+ <th>Feature</th>
+ <th>Chrome</th>
+ <th>Firefox (Gecko)</th>
+ <th>Internet Explorer</th>
+ <th>Opera</th>
+ <th>Safari</th>
+ </tr>
+ <tr>
+ <td>Basic support</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ </tr>
+ </tbody>
+</table>
+</div>
+
+<div id="compat-mobile">
+<table class="compat-table">
+ <tbody>
+ <tr>
+ <th>Feature</th>
+ <th>Android</th>
+ <th>Chrome for Android</th>
+ <th>Firefox Mobile (Gecko)</th>
+ <th>IE Mobile</th>
+ <th>Opera Mobile</th>
+ <th>Safari Mobile</th>
+ </tr>
+ <tr>
+ <td>Basic support</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ <td>{{CompatVersionUnknown}}</td>
+ </tr>
+ </tbody>
+</table>
+</div>
+
+<h2 id="Zie_ook">Zie ook</h2>
+
+<ul>
+ <li>{{jsxref("undefined")}}</li>
+ <li>{{jsxref("NaN")}}</li>
+</ul>