Final answer:
A Turing machine is a theoretical device capable of simulating any computer algorithm. It can solve the halting problem, which asks whether a given program will eventually halt or run forever.
Step-by-step explanation:
The subject of this question is Turing machine.
A Turing machine is a theoretical device presented by Alan Turing in 1936 that can compute anything that is computable. It is capable of simulating any computer algorithm, making it a universal computing machine. It consists of an infinite tape divided into cells, a read/write head, and a set of rules that determine its behavior.
For example, the Turing machine can solve the halting problem, which is a famous unsolvable problem in computer science. The halting problem asks whether a given program, when executed on a Turing machine, will eventually halt or run forever. Turing machines can provide answers to the halting problem for some programs, but not for all programs.