👉 clr is a free, open-source software library for C#. It provides a high-level programming model that can be used with C#, Visual Basic, or any other language. The CLR (Common Language Runtime) allows developers to write code in one language and run it on another, making the development process more efficient and easier. The CLR is an extension of Microsoft's .NET Framework, which was released in 2005 as a major release of Visual Studio. It provides a set of tools