It's safe to say an object is an instance or instantiation of a class. "instance" is used in more ways than this, so object and instance aren't quite equivalent, but they're close enough for most conversations.
A good question is never answered. It is not a bolt to be tightened into place but a seed to be planted and to bear more seed toward the hope of greening the landscape of the idea. John Ciardi
Originally posted by Terry Rickson: H It creates a button object but the variable b is the instance variable of the Button object.
Sorry, but that's incorrect terminology. An instance variable is a member variable of an object, used in contrast to class or static variable. "b" is a variable that refers to an object; that object is an instance of Button. But based on that one line of code, we can't tell if "b" is an instance variable or a local variable.