DFA M = (Q, S , d , q 0 , F), where Q = a finite set of states, one of which is designated the initial state or start state , and some of which are designated as final states . S = a set of finite characters, alphabet of possible input symbols. d = A finite set of transitions that specifies for each state and for each symbol of the input alphabet, which state to go to next. Transition d : Q ́ S à Q q 0 = starting state. F = a set of accepting states (a subset of Q i.e. F Í Q ).