SOLID

Solid Principles of Object Oriented Programming to make software designs more understandable, flexible and maintenable

SRP

Single Responsibility Principle

A class should've a single responsibility

Open Closed Principle

Types should be open for extension, but closed for modification

Liskov Subsitution Principle

Objects in a program should be replaceable with instances of their sub-type without altering correctness of that program

Interface Segregation Principle

Many client-specific interfaces are better than one general-purpose interface

Dependency Inversion Principle

Depend on abstractions not on concrete types