Description:

The Glorious Glasgow Haskell Compilation System (GHC) is a robust,
fully-featured, optimising compiler for the functional programming
language Haskell 98. GHC compiles Haskell to either native code or
C. It implements numerous experimental language extensions to Haskell,
including concurrency, a foreign language interface, several
type-system extensions, exceptions, and so on. GHC comes with a
generational garbage collector, a space and time profiler, and a
comprehensive set of libraries.

Haskell 98 is "the" standard lazy functional programming language.
More info plus the language definition is at http://www.haskell.org/.