Template:Formal languages and grammars

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Automata theory: formal languages and formal grammars
Chomsky
hierarchy
Grammars Languages Minimal
automaton
Type-0 Unrestricted Recursively enumerable Turing machine
n/a (no common name) Recursive Decider
Type-1 Context-sensitive Context-sensitive Linear-bounded
n/a Indexed Indexed Nested stack
n/a Tree-adjoining etc. (Mildly context-sensitive) Embedded pushdown
Type-2 Context-free Context-free Nondeterministic pushdown
n/a Deterministic context-free Deterministic context-free Deterministic pushdown
Type-3 Regular Regular Finite
n/a Star-free Counter-Free
Each category of languages or grammars is a proper subset of the category directly above it,
and any automaton in each category has an equivalent automaton in the category directly above it.