Class and Object are two pillars of Java programming language. There are multiple way you can describe Class in Java, for some one  Class is a user defined type, for others it's blueprint to create objects and for few of other it's just a way to model real world entity. Questions comes why do we need Class in Java, well one thing I can think of is to combine multiple types into one structure. Class and Object along with core OOPS concept e.g. Abstraction, Encapsulation, Inheritance and Polymorphism is first thing any Java programmer learn. I have just finished a basic Java presentation on Class for beginners which gives introduction of What is Class in Java and details some important details about Java Classes.