In Scheme, the lambda function is just a way of defining a function without giving it a name. Andy Balaam explains how to use lambda, and takes us through some mind-bending examples of the power of functions in Scheme. If you're new to Scheme, try http://youtu.be/byofGyW2L10 first. The slides for this video are here: http://www.artificialworlds.net/blog/2012/06/26/scheme-6-lambda-video/