- Consist of a finite number of
*states*and*transitions* - Transitions are labelled with input characters.
- There is one
*start state*. - A subset of the states are called
*final states*. - A finite state automaton starts in the start state, and for each input symbol follows an edge labelled with that symbol.
- It
*accepts*an input string iff it ends up in a final state. - Examples: Blackboard.