# Backbone's UMD

```javascript
(function(root, factory) {
  if (typeof define === 'function' && define.amd) {
    define(['underscore', 'jquery', 'exports'], function(_, $, exports) {
      root.Backbone = factory(root, exports, _, $);
    });
  } else if (typeof exports !== 'undefined') {
    var _ = require('underscore');
    factory(root, exports, _);
  } else {
    root.Backbone = factory(root, {}, root._, root.$);
  }
}(this, function(root, Backbone, _, $) {
  // Backbone…
}));
```
