Browserify is installed globally through npm and gives you a command line tool for running Browserify and generating output files. Run the following command:
$ npm install --global browserify
You should now have access to the browserify command. Let's go ahead and use it in a basic example.
Say we're working on a project and we'd like to take advantage of Underscore, a utility belt library full of useful JavaScript functions. It's also available on npm, so the first step is to install it.
$ npm install --save underscore
The --save flag will add Underscore as a dependency to your package.json file.
Now we can write some client side JavaScript that will require Underscore, in app.js:
var _ = require('underscore');
console.log(_.max([1,2,3,4,5]));
If you were to try to run this in a browser now it would fail, because there is no global require function available. Once we have our code, we need to run it through Browserify to generate a browser specific file that defines a require function and deals with the dependencies for us.
To generate a bundled JavaScript file, we need to pass Browserify the main file in our application. It will then recursively go through each file and its dependencies.
$ browserify app.js --output bundle.js
This instructs Browserify to start parsing at app.js and then output to bundle.js. Now we can add bundle.js to our HTML file:
<!doctype html>
<html>
<head>
<title>Browserify Test 1</title>
<script src="bundle.js"></script>
</head>
<body>
...
</body>
</html>
And if you look in your console you should see the number '5' logged to your screen. It worked!