acceptor

automaton

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July 23, 2026

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Automata theory is the study of the principles behind electromechanical devices called automata, which convert information according to a set procedure. These devices can range from simple mechanisms like pendulum clocks, where states are determined by the pendulum's swing, to complex systems like computers that respond to external inputs and events.1

Automata can be classified as transducers, which have both input and output, or acceptors, which recognize or accept input words without producing output. Acceptors halt in a special "final state" if the input is valid. The theory connects different types of automata to grammars, such as finite-state acceptors corresponding to regular languages and linear-bounded acceptors to context-sensitive grammars.234

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automata theory
Classification of automata
…principal classes are transducers and acceptors. In automata theory, a transducer is an automaton with input and output; any Turing machine for computing a partial recursive function, as previously described, can stand as an example. An acceptor is an automaton without output that, in a special sense, recognizes or accepts…
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…principal classes are transducers and acceptors. In automata theory, a transducer is an automaton with input and output; any Turing machine for computing a partial recursive function, as previously described, can stand as an example. An acceptor is an automaton without output that, in a special sense, recognizes or accepts…
Read More