oop - Difference between object and instance

Question

I know this sort of question has been asked before, but I still feel that the answer is too ambiguous for me (and, by extension, some/most beginners) to grasp.

I have been trying to teach myself broader concepts of programming than procedural and basic OOP. I understand the concrete concepts of OOP (you make a class that has data (members) and functions (methods) and then instantiate that class at run time to actually do stuff, that kind of thing).

I think I have a handle on what a class is (sort of a design blueprint for an instance to be created in its likeness at compile time). But if that's the case, what is an object? I also know that in prototype based languages, this can muck things up even more, but perhaps this is why there needs to be a clear distinction between object and instance in my mind.

Beyond that, I struggle with the concepts of "object" and "instance". A lot of resources that I read (including answers at SO) say that they are largely the same and that the difference is in semantics. Other people say that there is a true conceptual difference between the two.

Can the experts here at SO help a beginner have that "aha" moment to move forward in the world of OOP?

Note: this isn't homework, I don't go to school - however, I think it would help people that are looking for homework help.

Answer 1

A blueprint for a house design is like a class description. All the houses built from that blueprint are objects of that class. A given house is an instance.