An introduction, overview, and comparison of three similar interactive application architecture patterns: the Model-View-Controller, Model-View-Presenter, and Presentation-Abstraction-Control pattern.

http://ctrl-shift-b.blogspot.com/2007/08/interactive-application-architecture.html
An article on Separation of Concerns which refers to the establishment of logical boundaries to define and delineate purpose.

http://ctrl-shift-b.blogspot.com/2008/01/art-of-separation-of-concerns.html