Use Case Classics
http://207.5.16.194/content/view/12/2/

Kass, Andrew
BA Collective
2007

Abstract:

A use case is a detailed description of a user's interaction with a system. That's it. It's pretty simple; somewhat general, rather vague. That's the way it should be. A use case really amounts to nothing more than plain old 'documentation.' It can be applied to a business process, a complex software system, your morning routine, a wedding ceremony, or a historical event. The only requirements are an 'actor' and an object to be acted upon.