Commutative diagram

Given a number of functions, a commutative diagram shows that in many cases, applying different functions, perhaps in a different order gives the same result;

Functions can be chained, Mathematician talk about composing them:

That way, it is possible to create a new function, which first applies f, then g, and call it h
But h can of course be any other path as well. A diagram is called commutative diagram, if it doesn't matter what path is chosen to get from A to C.

Category:Mathematics