C# is object-oriented .NET programming languages. Since it is object-oriented so it allows you to build reusable components for a wide variety of application types.
Microsoft introduced C# on June 26th, 2000 and it became a v1.0 product on Feb 13th 2002. The name "C sharp" was inspired by musical notation where a sharp indicates that the written note should be made a semitone higher in pitch.
The most recent version is C# 5.0, which was released on August 15, 2012.