During its Build conference, Microsoft announced that it is releasing two dozen .NET development tools under an open source license. It will also create an organization named the .NET foundation to oversee the continued development of those tools. The newly open source tools include ASP.Net, the Entity Framework, the Roslyn.Net Compiler Platform, VB, C#, the .Net Micro Framework and .Net Rx.
Once known as a fierce enemy of the open source movement, Microsoft has been reaching out to the open source community and developers in recent years. Many industry watchers see this as a very significant move.
According to Microsoft, 6 million developers use .NET, and it is installed on 1.8 billion devices.