A Turing Machine is not a specific machine or a class of machines, but a concept defined in the language of mathematics, a tool invented to answer the ultimate questions of mathematicians of the 20th century about mathematics. Its purpose is to abstract and simplify the complex mathematical activities conducted in the human brain.
Defining a Turing Machine requires seven sets, of which the two most important are "a finite non-empty set of states" and "a finite non-empty set of symbols." The former represents "the types of symbols that the machine can read and write on the tape" and is also called the "number of colors." The latter stands for "the states that can occur inside the machine," known as the "number of states"—this can be understood simply as the machine having "gears" like a car.
