Common Language Runtime

The Common Language Runtime (CLR) is the virtual machine component of Microsoft's .NET framework and is responsible for managing the execution of .NET programs. In a process known as just-in-time (JIT) compilation, the CLR compiles the intermediate language code known as CIL into the machine instructions that in turn are executed by the computer's CPU. The CLR provides additional services including memory management, type safety and exception handling. All programs written for the .NET framework, regardless of programming language, are executed by the CLR.

The CLR is Microsoft's implementation of the Common Language Infrastructure (CLI) standard.

What is .Net Framework 4.0

The .NET Framework (pronounced dot net) is a software framework that runs primarily on Microsoft Windows. It includes a large library and supports several programming languages which allows language interoperability (each language can use code written in other languages). Programs written for the .NET Framework execute in a software environment (as contrasted to hardware environment), known as the Common Language Run time (CLR), an application virtual machine that provides important services such as security, memory management, and exception handling. The class library and the CLR together constitute the .NET Framework.

The .NET Framework's Base Class Library provides user interface, data access, database connectivity, cryptography, web application development, numeric algorithms, and network communications. Programmers produce software by combining their own source code with the .NET Framework and other libraries. The .NET Framework is intended to be used by most new applications created for the Windows platform. Microsoft also produces a popular integrated development environment largely for .NET software called Visual Studio.