Most Android developers will use Java to write their apps. Java is an object oriented programming language. But what precisely does that mean?

SOLID is an acronym that represents five design principles in object-oriented programming (OOP). These principles aim to make software systems more maintainable, flexible, and easily understood.

Kevlin Henney takes a philosophical approach to encapsulation, polymorphism and inheritance, and explains what it means to write Java programs according to his view on OOP.

The beginner-friendly bundle will introduce you to object-oriented programming, Java programming, Java design patterns, and more.

And the Fundamentals of Object-Oriented Programming: Java & intelliJ course gives you a solid intro to object-oriented programming.