• Single Responsibility Principle (SRP)
  • Every software component should have one and only one reason to change - Uncle Bob
  • Every software component should have one and only one responsibility
    • Component can be a class, method, or module
  • Cohesion and Coupling - High Cohesion, Low Coupling helps attain better adherence to the SRP
    • Cohesion is the degree to which the various parts of a software component are relate
    • Coupling is defined as the level of inter dependency between various software components
• Open-Closed Principle - Open for Extension, Closed for Modification
• Liskov Substitution Principle - Objects should be replaceable with their subtypes without affecting the correctness of the program
• Interface Segregation Principle - No client should be forced to depend on methods it does not use
• Dependency Injection Principle - High-level modules should not depend on low-level modules. Both should depend on abstractions.
  • Abstractions should not depend on details. Details should depend on abstractions