Turing machine

Definition

An abstract computing machine that has a finite number of possible internal states and operates on an infinite memory tape by first reading a symbol from a cell in the tape, and then, deterministically, based on that symbol and the machine’s state, writing a symbol in that cell, moving to a neighboring cell, and/or changing state.

Etymology

Named after English mathematician, logician, and cryptographer Alan Turing (1912–1954), who introduced the concept in 1936 to give a mathematically precise definition of computability.

Example Sentences

• "Another class, P, is a subset of NP, and includes all decision problems that can be solved by a (deterministic) Turing machine in polynomial time."