Question

The Practical Module pattern accepts this as a global:

(function( global )
  var Module = ...
  ...
  ...

  global.Module = Module;
})( this );

What’s the rational behind this decision?

The same goes for the Practical Constructor.

Answer 1

The code that you quote is technically equivalent to:

(function()
  var Module = ...
  ...
  ...

  this.Module = Module;
})();

and if it’s used as intended, outside of a constructor or method, then this will refer to the global object (such as window). By using the name global instead of this to refer to it, the code makes it more explicit that this is what’s happening. (You have to admit, “global” is a clearer name for the global object than “this“!)