JAVA Object
Class is a blueprint of an object. Class contains state and behaviour of an object. State means variables and behaviour means methods. All the objects are stored in heap memory in JVM in runtime which is called garbage collectable. Variables: Variables are of 2 types : Primitive Variables and reference Variables. Primitive Variables: Instance variables means variables of an object which vary from object to object. Which are defined by type of variable and name of variable like below . Variables have different sizes like cups in Starbucks when you ask a cup of capuchin they will ask small or medium or large. Similarly java primitive variables have different sizes like byte << short << int << long ...