Before the .NET 5 Microsoft maintain three frameworks in .NET: .NET Framework, .NET Core, and Mono/Xamarin. But in .NET 5 club .NET Framework, .NET Core, Mono/Xamarin together. Single SDK, One BCL and Unified toolchain : We can build any type of application using single SDK, One BCL. Unified toolchain: VS Code and .NET CLI using cross platform development. Cross Platform Native UI Cross Platform Web UI Cloud Native Invesment Continue Improvement in speed, size, diagnostics, Azure Services