SOLID

Introduced by Robert C. Martin, SOLID consists of five design principles for object-oriented programming: Single Responsibility, Open/Closed, Liskov Substitution, Interface Segregation, and Dependency Inversion. These guidelines dictate how classes and modules should be structured to ensure code remains maintainable, extensible, and testable during growth. Each principle addresses specific design aspects, including class responsibilities, change management, sub-type behavior, interface shaping, and module dependencies, providing a general vocabulary for achieving high-quality object-oriented design in software development.