What is an instance variable

Answer 1

A variable access through object (Or a variable defined inside a class Or a variable belonging to the object) is called an instance variable.

Answer 2

Roughly speaking, it's the same as a primitive (i.e. non-method) instance member.

Answer 3

A variable that is not static. It therefore does not belong to the class itself, but a single instance of the class. That is, an object you create.