# Beta reduction

### From HaskellWiki

Revision as of 19:49, 1 February 2007 by BrettGiles (Talk | contribs)

A *beta reduction* (also written *β reduction*) is where you actually apply a lambda function to an expression to generate a result.

For example, suppose we have

2*x*x + y

x

2*7*7 + y

We have thus performed a *beta reduction*.

Also see Lambda calculus and the wikipedia lambda calculus article.