What the Heck is an Algorithm?

An algorithm is a mathematical procedure used to solve a problem in a series of steps. Algorithms usually include loops of steps called iterations. This means the results of the calculation are used to begin the calculation again. Those results become the new start, over and over, until a specified limit. The algorithm provides these steps in such a way that they can be repeated by a computer.

A researcher enters the input data. The computer then performs hundreds or even thousands of calculation loops in very little time.

A simple example is the Euclidean algorithm, which is used to find the highest common factor of two positive integers.

Use the Euclidian algorithm to find the highest common factor of 54 and 930:

Divide the smaller number into the larger number.
930/54 = 17
Remainder of 12

Divide the remainder into the smaller number.
54/12 = 4
remainder of 6

Divide the second remainder into the first remainder.
12/6 = 2
remainder of 0

Continue dividing each remainder into the previous one until you get a remainder of 0. In this case, the highest common factor of 930 and 54 is 6.—Diane Boudreau