Introduction
Functional programs are like mathematical expressions that are "executed" by simplifying them as much as possible. Functional languages are also tied together by featuring function values that are as easy to manipulate as more common data types, allowing them to be combined in interesting ways.
HaskellLanguage (the archetype of a purely functional language)
MlLanguage The oldest functional languages are the family of Lisp languages, of which the most notable variants are
MultiParadigmLanguages usually emphasize functional programming.
"Why Functional Programming Matters", by John Hughes