For each state, there is a transition arrow leading out to a next state for both 0 and 1. The automaton takes a finite sequence of 0s and 1s as input. In this example automaton, there are three states: S 0, S 1, and S 2 (denoted graphically by circles). The figure illustrates a deterministic finite automaton using a state diagram. In search of the simplest models to capture finite-state machines, Warren McCulloch and Walter Pitts were among the first researchers to introduce a concept similar to finite automata in 1943. Deterministic refers to the uniqueness of the computation run. In the theory of computation, a branch of theoretical computer science, a deterministic finite automaton ( DFA)-also known as deterministic finite acceptor ( DFA), deterministic finite-state machine ( DFSM), or deterministic finite-state automaton ( DFSA)-is a finite-state machine that accepts or rejects a given string of symbols, by running through a state sequence uniquely determined by the string. For example, the string '1001' leads to the state sequence S 0, S 1, S 2, S 1, S 0, and is hence accepted. The state S 0 is both the start state and an accept state. An example of a deterministic finite automaton that accepts only binary numbers that are multiples of 3. The term may also refer to drug-facilitated sexual assault.
