The NotificationCenter is an implementation of the Observer Pattern in C#. With it you can post and receive notifications without having to know who will receive. This is handy in creating abstracted systems, such as an input controller that only knows about "MoveForward" or "Jump", and doesn't care if it's coming from a joystick, keyboard, or an automated script.
There's a demo of all the features here.
There's also an simple example of abstracted input here.
