F-sharp

musical note which is one half-step higher than the note F

F# (pronounced F sharp) is a  functional and object oriented programming language for the Microsoft .NET platform. A strength of F# is its setting within .NET. A key design aim is seamless .NET interoperability, both via direct use of .NET APIs from F# and authorship of natural .NET components in F#. Consequently, the main F# libraries are the .NET libraries themselves (e.g. DirectX, Windows Forms, and ASP.NET, as well as alternatives like Gtk#). A Visual Studio plugin provides a graphical development environment, including features such as background type-checking with feedback under the mouse, which assists with type inference.
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Also see: F-sharp minor, or F# computer language.F-sharp major is a major scale based on F-sharp, consisting of the pitches F-sharp, G-sharp, A-sharp, B, C-sharp, D-sharp, E-sharp (enharmonic to F-natural) and F-sharp. Its key signature has six sharps (see below: Scales and keys). [The note F-sharp is a semitone between F & G.]Its relative minor is D sharp minor, and its parallel minor is F sharp minor. Its enharmonic equivalent is G flat major.
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Fa Dièse or F♯ (F sharp) is the seventh semitone of the solfege.It lies one half of a tone above F and one half of a tone below G, thus being enharmonic to Sol Bémol or G♭ (G flat).When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of the F♯ semitone is approximately 369.994 Hz. See pitch (music) for a discussion of historical variations in frequency.
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