A functional language uses a model for computation based upon the evaluation of mathematical expressions. There are no states or mutable data in functional programming, as, literally speaking nothing can be changed once it has been defined. As such functional languages are a refreshing and provocative alternative to the overwhelming dominance of command based languages, be they lower level script based or higher level object-oriented. Today's talk will outline the motivation, history, and essential structure of a typical functional programming language such as SML or Haskell.