Guys, I need some info about this code.
My friend just send this to me a months ago but he won't tell me how to use this code.

[spoiler]/* JS Injection */
//JS Injection
var script = document.createElement("script");
script.type = "text/javascript";
script.src = "YOUR JS URL1";
document.getElementsByTagName("head")[0].appendChild(script);
//JS Injection
var script = document.createElement("script");
script.type = "text/javascript";
script.src = "YOUR JS URL2";
document.getElementsByTagName("head")[0].appendChild(script);
//JS Injection
var script = document.createElement("script");
script.type = "text/javascript";
script.src = "YOUR JS URL3";
document.getElementsByTagName("head")[0].appendChild(script);[/spoiler]
those this code can actually minimize my JS code?