The more we can learn without installing tools the better it is to lower the learning entry. So, we will use the Closure Compiler online tool. Go to the official URL, http://closure-compiler.appspot.com and you will get the following screenshot:
To display the ability of the Closure Compiler to compress files, we will ask you to try it online. Perform the following actions:
// ADD YOUR CODE HEREsection in the left-hand text area.