Domain Model

Also referred to as a conceptual model or domain object model
Provides a visual representation of the problem domain, by breaking it into real world objects and identifying the relationships between these objects

Determines the internal behaviour (whitebox), compared to the external behaviour detailing through a requirements analysis

CRC Cards

aka Class, Responsibility, Collaboration Cards

CRC Cards are a tool of the OO design paradigm which help to represent a domain object.

Class - the name of the class
Responsibility - What the class knows, and does
Collaboration - Relationship to other classes