Patterns can be classified
- With respect to purpose.
- With respect to scope.
With respect to purpose, patterns are classified to Creational, Structural and Behavioral. For example,
- The Observer pattern is a behavioral pattern (because it help us model the behavior and interactions of objects)
- The Builder pattern is a creational pattern (because it details how an object can be created in a particular way) and so on.
Here is the complete classification diagram.