SOLID Principles

1. Single Responsibility Principle (SRP)

Definition: A class should have only one reason to change, meaning that it should have only one responsibility.

Implication: Breaking down a system into smaller, more focused classes can make it easier to understand, maintain, and modify.

2. Open/Closed Principle (OCP)

Definition: Software entities (classes, modules, functions) should be open for extension but closed for modification.

Implication: You can add new functionality without altering existing code, promoting the use of interfaces, abstract classes, and design patterns like the Strategy Pattern.

3. Liskov Substitution Principle (LSP)

Definition: Subtypes must be substitutable for their base types without altering the correctness of the program.

Implication: Objects of a superclass should be able to be replaced with objects of a subclass without affecting the functionality of a program.

4. Interface Segregation Principle (ISP)

Definition: A class should not be forced to implement interfaces it does not use.

Implication: Interfaces should be specific to the needs of the client. Large, monolithic interfaces should be split into smaller, client-specific interfaces.

5. Dependency Inversion Principle (DIP)

Definition: High-level modules should not depend on low-level modules. Both should depend on abstractions.

Implication: Abstractions (interfaces or abstract classes) should not depend on details; details should depend on abstractions. This promotes the use of dependency injection and inversion of control containers.