Common Language Runtime

Program execution
General topics
Runtime system Runtime library Executable Compiler Interpreter Virtual machine Source code Object code Bytecode Machine code
Specific runtimes
Android Runtime (ART) crt0 Common Language Runtime (CLR) Dalvik Java virtual machine (JVM)

The Common Language Runtime (CLR), the virtual machine component of Microsoft's .NET framework, manages the execution of .NET programs. A process known as just-in-time compilation converts compiled code into machine instructions which the computer's CPU then executes. The CLR provides additional services including memory management, type safety, exception handling, garbage collection, security and thread management. All programs written for the .NET framework, regardless of programming language, are executed by the CLR. All versions of the .NET framework include CLR.

CLR implements the Virtual Execution System (VES) as defined in the Common Language Infrastructure (CLI) standard, initially developed by Microsoft itself. A public standard defines the Common Language Infrastructure specification.

The CLR converts CIL (Common Intermediate Language) to native code.

Overview of the Common Language Runtime release history

CLR version	.NET version
1.0	1.0
1.1	1.1
2.0	2.0, 3.0, 3.5
4	4, 4.5, 4.6

Benefits

The runtime provides the following benefits:

• Performance improvements.
• The ability to easily use components developed in other languages.
• Extensible types provided by a class library.
• Language features such as inheritance, interfaces, and overloading for object-oriented programming.
• Support for explicit free threading that allows creation of multithreaded, scalable applications.
• Support for structured exception handling.
• Support for custom attributes.
• Garbage collection.
• Use of delegates instead of function pointers for increased type safety and security. For more information about delegates, see Common Type System.

See also

• Common Intermediate Language
• List of CLI languages
• Java virtual machine

External links

• Functions of Common Language Runtime
• Components of Common Language Runtime
• Components of CLR
• Overview of the .NET Framework 4.0
• .NET Framework Conceptual Overview