In computer science, a pushdown automaton(PDA) is a type of automaton that employs a stack. Pushdown automata are used in theories about what can be computed by machines. They are more capable than finite-state machines but less capable than Turing machines.
A deterministic pushdown automaton is a variation of the pushdown automata. The class of deterministic pushdown automata accepts the deterministic CFL a proper subset of context free language.