Today is a huge day for .NET! We’re happy to announce that .NET Core will be open source, including the runtime as well as the framework libraries. This is a natural progression of our open source efforts, which already covers the managed compilers as well as ASP.NET: .NET Core is a modular development stack that is the foundation of all future .NET platforms It’s already used by ASPNET Core 5 and NET Native I’ll go into more detail on what NET Core is and how it relates to the NET Framework in a following blog post.
Source: Tech