- S: Single Responsibility Principle
- O: Open/Closed Principle
- L: Liskov’s Substitution Principle
- I: Interface Segregation Principle
- D: Dependency Inversion Principle

In software development, Object-Oriented Design plays a crucial role when it comes to writing flexible, scalable, maintainable, and reusable code. There are so many benefits of using OOD but every developer should also have the knowledge of the SOLID principle for good object-oriented design in programming. The SOLID principle was introduced by Robert C. Martin, also known as Uncle Bob and it is a coding standard in programming.

The SOLID principle helps in reducing tight coupling. Tight coupling means a group of classes are highly dependent on one another which you should avoid in your code. Opposite of tight coupling is loose coupling and your code is considered as a good code when it has loosely-coupled classes. Loosely coupled classes minimize changes in your code, helps in making code more reusable, maintainable, flexible and stable.