Non Deterministic Pushdown automata

A non-deterministic PDA is used to generate a language that a deterministic automata cannot generate. It is more powerful than a deterministic PDA. So, a push down automata is allowed to be non-deterministic.

A non-deterministic pushdown automaton is a 7-tuple

M = (Q,Σ,Γ,δ,q0,Z0,F)

Q- It is the finite set of states,
Σ - finite set of input alphabet,
Γ - finite set of stack alphabet,
δ - transition function,
q0 - initial state,
Z0 - stack start symbol,
F - finite states.