Algorithms as machines

To solve problems occurring in the real world, computing scientists devise algorithms. These algorithms are programmed on computers and used to solve the problems. But computing scientists also talk about ‘machines’ of various kinds, such as Turing machines, Mealy machines and von Neumann machines. (These are quite different from actual computers.) This article examines how algorithms turn into machines. The problems considered are the very elementary ones of addition, multiplication and factoring.