C# is a programming language from Microsoft designed specifically to target the .NET Framework. Microsoft's .NET Framework is a runtime environment and class library that dramatically simplifies the development and deployment of modern, component-based applications.
When the .NET Framework and C# language compiler were shipped in final form in January 2002, both the platform and programming language had already garnered much industry attention and widespread use among Microsoft-centric early adopters. Why this level of success? Certainly, the C# language and the .NET Framework address many of the technical challenges facing modern developers as they strive to develop increasingly complex distributed systems with ever-shrinking schedules and team sizes.
However, in addition to its technical merits, one of the main reasons for the success that the language and platform has enjoyed thus far is the unprecedented degree of openness that Microsoft has shown. From July 2000 to January 2002, the .NET Framework underwent an extensive public beta that allowed tens of thousands of developers to "kick the tires" of the programming environment. This allowed Microsoft to both solicit and react to developer community feedback before finalizing the new platform.
Additionally, the key specifications for both the language and the platform have been published, reviewed, and ratified by an international standards organization called the European Computer Manufacturers Association (ECMA). These standardization efforts have led to multiple third-party initiatives that bring the C# language and the .NET platform to non-Microsoft environments. They have also prompted renewed interest among academics in the use of Microsoft technologies as teaching and research vehicles.
Lastly, although the language and platform are shiny and new, the foundations for the C# language and the .NET Framework have been years in the making, reaching back more than half a decade. Understanding where the language and platform have come from gives us a better understanding of where they are headed.