What is an algorithm ?

An algorithm is a simple way to describe the resolution of a problem.

It explains step by step what to do to solve the problem , but not How to do it.

• Like a problem, an Algorithm always has a BEGINning and an END
• It's composed by several steps and each step solves a part of the problem.
• The more complex the problem, the more steps you need.
• Each task can be a smaller problem, with its own algorithm

What an algorithm is not...

• It's not a magic box. You have to understand the problem before you start the algorithm
• It's not a programming language. With a programming language you'll define how to solve the problem. But for some simple problems, algorithms are quite similar to a computing language.
• It's not a software. You don't need a computer and it's better to write it on a piece of paper
• It's not a gadget : it helps us to explain, simplify and solve complex questions.