Monad

A term taken from category theory and applied to functional programming concepts to provide a way to deal with local, single-thread state in a functional language without having to pass the state around explicitly as extra arguments to all the functions that deal with it (and requiring changing their signatures, etc.) See also Eugenio Moggi and a Learning Lounge course, Monads 101.

The FOLDOC entry.
A recent, in-depth, seemingly practical tutorial All About Monads.
Monads (thanks to Wayback Machine) (old link MIA), a collection of references to literature about monads (mostly computer science) by Lisa A. Walton (old home-page MIA).
About optimizing certain kinds of monads, see the work of Jonathan Sobel.
Categories List.

This page is linked from: Arrow Logic 101 Category Theory 101 Continuation-Passing Style Eugenio Moggi Linear Logic Linear Logic Comments Monads 101 Referential Transparency and State