SOLID

1. Single Responsibility Principle

1.1. There should never be more than one reason for a class to change

1.2. NEU: "A module should be responsible to one, and only one, actor"

1.3. Durch die Anforderungen eines Akteurs definierte Funktionalitäten und Datenstrukturen

2. Open Closed Principle

2.1. A class is open for enhancements but closed against modifications

3. Liskov Substitution Principle

3.1. A subtype behaves same as its base type

4. Interface Segregation Principle

4.1. Clients shall be not confused with details which they do not need

5. Dependency Inversion Principle

5.1. High-level classes must not depend on low-level classes, but both on interfaces

5.2. Interfaces must not depend on details, but details on interfaces

5.3. Schalter/Lampe Besipiel