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<h2>Table of Contents</h2>
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<p><a href="#synopsis_usage_and_example">Usage and example</a></p>
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<h1>Usage and example<span><a class="mark" href="#synopsis_usage_and_example" id="synopsis_usage_and_example">#</a></span></h1>
<h2>Usage<span><a class="mark" href="#synopsis_usage" id="synopsis_usage">#</a></span></h2>
<p><code>node [options] [V8 options] [script.js | -e "script" | - ] [arguments]</code></p>
<p>Please see the <a href="cli.html#cli_command_line_options">Command Line Options</a> document for more information.</p>
<h2>Example<span><a class="mark" href="#synopsis_example" id="synopsis_example">#</a></span></h2>
<p>An example of a <a href="http.html">web server</a> written with Node.js which responds with
<code>'Hello, World!'</code>:</p>
<p>Commands in this document start with <code>$</code> or <code>></code> to replicate how they would
appear in a user's terminal. Do not include the <code>$</code> and <code>></code> characters. They are
there to show the start of each command.</p>
<p>Lines that don’t start with <code>$</code> or <code>></code> character show the output of the previous
command.</p>
<p>First, make sure to have downloaded and installed Node.js. See <a href="https://nodejs.org/en/download/package-manager/">this guide</a>
for further install information.</p>
<p>Now, create an empty project folder called <code>projects</code>, then navigate into it.</p>
<p>Linux and Mac:</p>
<pre><code class="language-console">$ mkdir ~/projects
$ cd ~/projects
</code></pre>
<p>Windows CMD:</p>
<pre><code class="language-console">> mkdir %USERPROFILE%\projects
> cd %USERPROFILE%\projects
</code></pre>
<p>Windows PowerShell:</p>
<pre><code class="language-console">> mkdir $env:USERPROFILE\projects
> cd $env:USERPROFILE\projects
</code></pre>
<p>Next, create a new source file in the <code>projects</code>
folder and call it <code>hello-world.js</code>.</p>
<p>Open <code>hello-world.js</code> in any preferred text editor and
paste in the following content:</p>
<pre><code class="language-js">const http = require('http');
const hostname = '127.0.0.1';
const port = 3000;
const server = http.createServer((req, res) => {
res.statusCode = 200;
res.setHeader('Content-Type', 'text/plain');
res.end('Hello, World!\n');
});
server.listen(port, hostname, () => {
console.log(`Server running at http://${hostname}:${port}/`);
});
</code></pre>
<p>Save the file, go back to the terminal window, and enter the following command:</p>
<pre><code class="language-console">$ node hello-world.js
</code></pre>
<p>Output like this should appear in the terminal:</p>
<pre><code class="language-console">Server running at http://127.0.0.1:3000/
</code></pre>
<p>Now, open any preferred web browser and visit <code>http://127.0.0.1:3000</code>.</p>
<p>If the browser displays the string <code>Hello, World!</code>, that indicates
the server is working.</p>
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