https://khalilstemmler.com/articles/object-oriented/programming/4-principles/ 4 Principles of Object-Oriented Programming | Khalil Stemmler The four principles of object-oriented programming (abstraction, inheritance, encapsulation, and polymorphism) are features that - if used properly - can help us write more testable, flexible, and maintainable code. khalilstemmler.com 객체지향 4대 특성 추상화 (Abstrac..