1. Single Responsibility Principle. ( Single Responsibility Principle )
Note: the division of social production should be fine. Specific everyone the best only one thing (not a person and multiple roles), so if this person leave or resign, will not have an impact on production.
2. Open Closed Principle. (Open-Close Principle)
Note: People do not change, most change clothes under it, or painted light make-up (ha ha).
3. Richter substitution principle. (Liskov Substitution Principle)
Notes: It is a matter of principle CLASS determine the relationship, such as a square is a rectangle but a rectangle is not inherited. Ostrich is a bird, but the bird can not be inherited.
4. Interface Segregation principle. (The Interface Segregation Principle)
Note: An interface provides only the necessary functions of a class. In this way the successor does not need to achieve some unnecessary features. For example: When IBird (+ Fly ()), will be realized unnecessary Fly () when the ostrich inheritance.
5. Dependency Inversion Principle. ()