[In a similar vein, I was about to say:] Object-orientation is fundamentally just a way of organising programs. In most non-OO programming, you've got a bunch

[In a similar vein, I was about to say:] Object-orientation is fundamentally just a way of organising programs. In most non-OO programming, you've got a bunch of data, and a bunch of procedures that can operate on the data. The two are defined and considered somewhat separately, though they must fit together. In OOP, a kind of datum and the operations on it are instead designed, defined and used together, as essentially linked.