That’s a great question. Combinational logic is an example of something that computes that isn’t a state machine. You can compute Boolean algebra operations wit

That’s a great question. Combinational logic is an example of something that computes that isn’t a state machine. You can compute Boolean algebra operations with no notion of time, they’re essentially pure functions. That’s where it gets slightly confusing though. Just because a function is pure, does not mean that its implementation is not a state machine. For example, an algorithm to compute the greatest common denominator between two numbers is stateful, even if it has a pure functional interface.