• Design patterns are solutions to recurring problems in software engineering. Rather than a comprehensive solution, a design pattern is a description of a problem and a template of how to solve it. This template then becomes usable in many different contexts.

• study the problem and the solutions
• goal is to identify patterns among your requirements and architecture
• use pre-conceived solutions to the problem
• if design is composed of well-known patterns, it’s easy to:
  • share idea

Types