Science From Scratch: Algorithms

Written for Reporter magazine’s Science From Scratch column.

An algorithm is a recipe. When following a recipe for a chocolate fudge cake, for example, we carry out an ordered series of actions that takes a set of ingredients – flour, sugar, eggs, chocolate – and produces a cake. The recipe specifies which actions to perform and the order in which to do them. In mathematics and computer science, an algorithm relates a set of inputs to an output in much the same way that a cake recipe relates the ingredients to a cake. Some algorithms have become standard tools for common tasks such as sorting, searching, or finding the best routes between locations. Algorithms have also been around for a lot longer than computers: Euclid’s algorithm for finding the largest positive whole number that divides two others, for example, was recorded in 300 BC. More recently, “rogue algos” have been blamed for the stock market crash. But blaming an algorithm is like blaming a recipe – the responsibility lies with whoever asked for a cake when a brownie was needed instead.