 Let's have a look at finite state automata, or FSA for short. In this series of videos, we're going to look at how FSA are useful. Use them in an example to test for valid sentences, and then build our own automata to explore other uses. So, what do these words mean, finite state automata? Finite means that there are a limited number, as opposed to infinite, which means the number is unlimited. A state is a condition at a particular time, and automata is the plural for automaton, a machine that functions on its own following some simple instructions and rules. Therefore, a finite state automaton is a simple machine with a finite number of states. Let's have a look at the finite state automata, or FSA, or FSA, or FSA, or FSA, or FSA.