Can anyone please explain difference between finite state machine and finite automata?

Question

Can anyone please explain with example what is the difference between finite state machine and finite automata?

Answer 1

Both "Finite State Machine" FSM and "Finite Automata" (or Finite State Automata) FA means same, represents an abstract mathematical model of computation for the class of regular languages.

The word "Finite" significance the presence of the finite amount of memory in the form of the finite number of states Q (read: Finiteness of Regular Language).

Generally in formal-theory (or theory of computation), we prefer to use the word "Automata" – to emphasise that our machine is 'automatic' machine (self-moving: like our computer) — "automatic" in the sense that once you have been defined transition rules, you do not need to apply any explicit intelligent to process strings (you just need to refer transition rules at each step). Remember our ultimate aim behind defining transition machines is to automate the computational task (I think slightly different than another kind of mechanical machines whose purpose is to save energy e.g weaving machines).

By the way, automata or state-machines are a graphical representation to describe transition rules (that is comparatively easy sometimes). You can also use "Transition Tables" or "Transition function" like δ(q0, a) → q1. Basically, all uses for the same purpose just to define "Mappings".