An algorithm is a computational process that takes a problem instance and in a finite amount of time produces a solution. . . . It is hard to make the definition of algorithm more precise except by saying that a computational process is anything that can be done by a program for a computing machine, and in that case one must accept that a human being with paper and pencil is a kind of computing machine. Floyd and Beigel, The Language of Machines, Computer Science Press, W.H. Freeman, 1994, p. 444.

Website: http://www.augustana.ab.ca/~mohrj/courses/1998.fall/csc110/lecture_notes/turing_machines.html