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What is SOLID?

SOLID is a acronym for five principles of Object Oriented Design, and stands for:

• S - Single-responsibility Principle
• O - Open-closed Principle
• L - Liskov Substitution Principle
• I - Interface Segregation Principle
• D - Dependency Inversion Principle

⚠️ Here you will see only the main phrase about every principle. The best place to get this information is from the article The S.O.L.I.D Principles in Pictures wrote by Ugonna Thelma.

Single-Responsibility Principle (SRP)

A class should have one, and only one, reason to change. (Martin, n.d.)

The idea behind the Single-Responsibility Principle (SRP) is that a class or module has a single responsibility or task to perform (Boris, 2023).

Open-Closed Principle (OCP)

You should be able to extend a classes behavior, without modifying it. (Martin, n.d.)

Liskov Substitution Principle (LSP)

Derived classes must be substitutable for their base classes. (Martin, n.d.)

Interface Segregation Principle (ISP)

Make fine grained interfaces that are client specific. (Martin, n.d.)

Dependency Inversion Principle (DIP)

Depend on abstractions, not on concretions. (Martin, n.d.)

References

• Oloruntoba, Samuel. (2020, September 21). SOLID: The First 5 Principles of Object Oriented Design. Digital Ocean. <https://www.digitalocean.com/community/conceptual-articles/s-o-l-i-d-the-first-five-principles-of-object-oriented-design/>
• Martin, Robert C. (n.d.). The Principles of OOD. butUncleBob. <http://butunclebob.com/ArticleS.UncleBob.PrinciplesOfOod/>
• Bodin, Boris. (2023, September 9). Understanding SOLID Principles. Scub-Lab.<https://lab.scub.net/understanding-solid-principles-9a0181e68b88/>
• Thelma, Ugonna. (2020, May 18). The S.O.L.I.D Principles in Pictures. Ugonna Thelma.<https://medium.com/backticks-tildes/the-s-o-l-i-d-principles-in-pictures-b34ce2f1e898/>