Dr. Alan Kay on the Meaning of “Object Oriented Programming”. A friend and I were talking about Kay’s original intentions for OOP the other day, so I thought this link might be interesting to others, as well. It turns out, OOP is a lot less about encapsulated data and methods on the data, and a lot more about messages between “little computers”:

The original conception of it had the following parts.

• I thought of objects being like biological cells and/or individual computers on a network, only able to communicate with messages (so messaging came at the very beginning – it took a while to see how to do messaging in a programming language efficiently enough to be useful).

[…] OOP to me means only messaging, local retention and protection and hiding of state-process, and extreme late-binding of all things. It can be done in Smalltalk and in LISP. There are possibly other systems in which this is possible, but I’m not aware of them.