1. pushdown - Noun
2. pushdown - Adjective
pushdown (not comparable)
(computing) Describing a stack in which items are removed in a LIFO manner from the end at which they were added.
pushdown (plural pushdowns)
A pushdown automaton.
A linear bounded automaton is a device which is more powerful than a pushdown automaton but less so than a Turing machine. Source: Internet
Formally, the set of all context-free languages is identical to the set of languages accepted by pushdown automata (PDA). Source: Internet
Computations a step of the pushdown automaton In order to formalize the semantics of the pushdown automaton a description of the current situation is introduced. Source: Internet
Computations of the pushdown automaton are sequences of steps. Source: Internet
For each single pushdown automaton these two languages need to have no relation: they may be equal but usually this is not the case. Source: Internet
In general pushdown automata are nondeterministic meaning that in a given instantaneous description there may be several possible steps. Source: Internet