10.3. Minification

JavaScript minification reduces unnecessary characters from scripts without changing any functionality. These characters include whitespace, new lines, and comments. The better minifiers can interpret JavaScript. Therefore, they can safely shorten variables and function names, further reducing characters. Smaller file sizes are better because there’s less data to transfer over the network.

It’s not just JavaScript that can be minified. Stylesheets and HTML can also be processed. Stylesheets in particular tend to have a lot of redundant whitespace. Minification is something best done on deployment because you don’t want to be debugging any minified code. If there’s an error in production, try to reproduce it in a development environment first—you’ll find it much easier to debug the problem.