Purpose of Varias JS file Inside Ember Package

I have pulled ember with bower and I see various files. I do understand that I will have to add ember.min.js and ember-template-compiler.js to start working with ember. But I see other files that I am curious of.

ember 
  | - ember.debug.js
  | - ember.prod.js
  | - ember.testing.js

Can anyone describe purpose of these files?