A class that can be used only as a superclass of some other class; no objects of an abstract class may be created except as instances of a subclass.
The act of concentrating the essential or general qualities of similar things. Also, the resulting essential characteristics of a thing.
An object with its own thread of control.
A property of an association representing a whole-part relationship and (usually) life-time containment.
An investigation of a domain that results in models describing its static and dynamic characteristics. It emphasizes questions of “what,” rather than “how.”
Informally, a description of the organization, motivation, and structure of a system. ...