RequireJs – Define vs Require

Essentially, when you use require you are saying “i want this, but i want all its dependencies too”. So in the example below, we’re requiring A, but require will search for all dependencies and ensure they are loaded before continuing.

require(['a'], function(a) {
    // b, c, d, e will be loaded
});

// File A
define(['b','c','d','e'], function() {
    return this;
});

General rule of thumb is you use define when you want to define a module that will be reused by your application and you use require to simply load a dependency.