var script = document.createElement("script");
var head = document.getElementsByTagName('head').item(0);
script.src = fileUrl;
If you look carefully the name of the function is $include. It just makes it stand out other than that you could name it whatever you want. This just makes the code really clean and no more messy html files with 10 script tags to load all the files. It just makes life simpler if you have too many script files to load.