F# (pronounced F sharp) is a mixed functional and imperative programming language for the Microsoft .NET platform. F# was developed by Don Syme at Microsoft Research, and has a core language that is similar to that of the Ocaml language (itself a member of the ML programming language family).
F# is a research project to demonstrate how .NET enables interoperability between different programming paradigms. F# showcases a set of extensions to .NET's intermediate language IL, called ILX which demonstrate how a strict curried functional language may be compiled efficiently.