Instance Variable

A class variable without static modifier is called Instance Variable, It is unique to each object(instance) of the class and not shared between the class

Class Variable

Class variable can be declared any where in the class level using keyword static, These variable can only have one value when applied to various object.These variable can be shared by all class member since they are not connected to a specific instance

class Test {
    static int count = 0; // Class Variable
    int id;               // Instance Variable
}
count → one copy shared by all Test objects.
id → each Test object has its own value.