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230<li><a href="https://nodejs.org/docs/latest-v14.x/api/synopsis.html">14.x</a></li>
231<li><a href="https://nodejs.org/docs/latest-v13.x/api/synopsis.html">13.x</a></li>
232<li><a href="https://nodejs.org/docs/latest-v12.x/api/synopsis.html">12.x</a></li>
233<li><a href="https://nodejs.org/docs/latest-v11.x/api/synopsis.html">11.x</a></li>
234<li><a href="https://nodejs.org/docs/latest-v10.x/api/synopsis.html">10.x</a></li>
235<li><a href="https://nodejs.org/docs/latest-v9.x/api/synopsis.html">9.x</a></li>
236<li><a href="https://nodejs.org/docs/latest-v8.x/api/synopsis.html">8.x</a></li>
237<li><a href="https://nodejs.org/docs/latest-v7.x/api/synopsis.html">7.x</a></li>
238<li><a href="https://nodejs.org/docs/latest-v6.x/api/synopsis.html">6.x</a></li>
239<li><a href="https://nodejs.org/docs/latest-v5.x/api/synopsis.html">5.x</a></li>
240<li><a href="https://nodejs.org/docs/latest-v4.x/api/synopsis.html">4.x</a></li>
241<li><a href="https://nodejs.org/docs/latest-v0.12.x/api/synopsis.html">0.12.x</a></li>
242<li><a href="https://nodejs.org/docs/latest-v0.10.x/api/synopsis.html">0.10.x</a></li></ol></div>
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268      <details id="toc" open><summary>Table of contents</summary><ul>
269<li><a href="#usage-and-example">Usage and example</a>
270<ul>
271<li><a href="#usage">Usage</a></li>
272<li><a href="#example">Example</a></li>
273</ul>
274</li>
275</ul></details>
276
277      <div id="apicontent">
278        <h2>Usage and example<span><a class="mark" href="#usage-and-example" id="usage-and-example">#</a></span><a aria-hidden="true" class="legacy" id="synopsis_usage_and_example"></a></h2>
279<section><h3>Usage<span><a class="mark" href="#usage" id="usage">#</a></span><a aria-hidden="true" class="legacy" id="synopsis_usage"></a></h3>
280
281
282<p><code>node [options] [V8 options] [script.js | -e "script" | - ] [arguments]</code></p>
283<p>Please see the <a href="cli.html#options">Command-line options</a> document for more information.</p>
284</section><section><h3>Example<span><a class="mark" href="#example" id="example">#</a></span><a aria-hidden="true" class="legacy" id="synopsis_example"></a></h3>
285<p>An example of a <a href="http.html">web server</a> written with Node.js which responds with
286<code>'Hello, World!'</code>:</p>
287<p>Commands in this document start with <code>$</code> or <code>></code> to replicate how they would
288appear in a user's terminal. Do not include the <code>$</code> and <code>></code> characters. They are
289there to show the start of each command.</p>
290<p>Lines that don't start with <code>$</code> or <code>></code> character show the output of the previous
291command.</p>
292<p>First, make sure to have downloaded and installed Node.js. See
293<a href="https://nodejs.org/en/download/package-manager/">Installing Node.js via package manager</a> for further install information.</p>
294<p>Now, create an empty project folder called <code>projects</code>, then navigate into it.</p>
295<p>Linux and Mac:</p>
296<pre><code class="language-console"><span class="hljs-meta prompt_">$ </span><span class="language-bash"><span class="hljs-built_in">mkdir</span> ~/projects</span>
297<span class="hljs-meta prompt_">$ </span><span class="language-bash"><span class="hljs-built_in">cd</span> ~/projects</span></code> <button class="copy-button">copy</button></pre>
298<p>Windows CMD:</p>
299<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash"><span class="hljs-built_in">mkdir</span> %USERPROFILE%\projects</span>
300<span class="hljs-meta prompt_">> </span><span class="language-bash"><span class="hljs-built_in">cd</span> %USERPROFILE%\projects</span></code> <button class="copy-button">copy</button></pre>
301<p>Windows PowerShell:</p>
302<pre><code class="language-console"><span class="hljs-meta prompt_">> </span><span class="language-bash"><span class="hljs-built_in">mkdir</span> <span class="hljs-variable">$env</span>:USERPROFILE\projects</span>
303<span class="hljs-meta prompt_">> </span><span class="language-bash"><span class="hljs-built_in">cd</span> <span class="hljs-variable">$env</span>:USERPROFILE\projects</span></code> <button class="copy-button">copy</button></pre>
304<p>Next, create a new source file in the <code>projects</code>
305folder and call it <code>hello-world.js</code>.</p>
306<p>Open <code>hello-world.js</code> in any preferred text editor and
307paste in the following content:</p>
308<pre><code class="language-js"><span class="hljs-keyword">const</span> http = <span class="hljs-built_in">require</span>(<span class="hljs-string">'node:http'</span>);
309
310<span class="hljs-keyword">const</span> hostname = <span class="hljs-string">'127.0.0.1'</span>;
311<span class="hljs-keyword">const</span> port = <span class="hljs-number">3000</span>;
312
313<span class="hljs-keyword">const</span> server = http.<span class="hljs-title function_">createServer</span>(<span class="hljs-function">(<span class="hljs-params">req, res</span>) =></span> {
314  res.<span class="hljs-property">statusCode</span> = <span class="hljs-number">200</span>;
315  res.<span class="hljs-title function_">setHeader</span>(<span class="hljs-string">'Content-Type'</span>, <span class="hljs-string">'text/plain'</span>);
316  res.<span class="hljs-title function_">end</span>(<span class="hljs-string">'Hello, World!\n'</span>);
317});
318
319server.<span class="hljs-title function_">listen</span>(port, hostname, <span class="hljs-function">() =></span> {
320  <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`Server running at http://<span class="hljs-subst">${hostname}</span>:<span class="hljs-subst">${port}</span>/`</span>);
321});</code> <button class="copy-button">copy</button></pre>
322<p>Save the file, go back to the terminal window, and enter the following command:</p>
323<pre><code class="language-console"><span class="hljs-meta prompt_">$ </span><span class="language-bash">node hello-world.js</span></code> <button class="copy-button">copy</button></pre>
324<p>Output like this should appear in the terminal:</p>
325<pre><code class="language-console">Server running at http://127.0.0.1:3000/</code> <button class="copy-button">copy</button></pre>
326<p>Now, open any preferred web browser and visit <code>http://127.0.0.1:3000</code>.</p>
327<p>If the browser displays the string <code>Hello, World!</code>, that indicates
328the server is working.</p></section>
329        <!-- API END -->
330      </div>
331    </div>
332  </div>
333</body>
334</html>
335