Microsoft's F# offers a true functional programming language for the .NET platform. The "functional programming" approach creates exceptionally stable, fault-tolerant code that's especially efficient for the concurrent programming requirements of multi-processor and high-availability applications. F# builds on the legacy of Erlang, Haskel, and OCaml, adding full .NET support and easy interoperability with C# and other .NET platform features. F# in Action introduces the F# language, but it goes well beyond the standard tutorial and reference approach. F# expert Amanda Laucher draws on her extensive experience deploying F#-based solutions to show you how to use F# in real, day-to-day work. You'll see "Greenfield" examples, where you build new F# programs from scratch. You'll also dig into "Brownfield" scenarios, where you integrate F# code into in-place systems. Along the way, you'll master the functional programming style and learn where and how to apply it most effectively.