C# is a general-purpose, multi-paradigm programming language developed by Microsoft in 2002. It is a statically typed, compiled language, meaning the code is converted into machine code before it is executed.

.NET is a software framework developed by Microsoft that provides a common language runtime (CLR) and a set of libraries that can be used to develop applications. The CLR is responsible for managing the execution of C# code and providing services such as garbage collection.