Visual overview of the Common Language Infrastructure (CLI)

The Common Language Infrastructure (CLI) is an open specification developed by Microsoft that describes the executable code and runtime environment that form the core of the Microsoft .NET Framework. The specification defines an environment that allows multiple high-level languages to be used on different computer platforms without being rewritten for specific architectures. Image File history File links Overview_of_the_Common_Language_Infrastructure. ... Image File history File links Overview_of_the_Common_Language_Infrastructure. ... In engineering and manufacturing, the term specification has the following meanings: Technical requirement A specification is a set of requirements. ... Microsoft is one of few companies engaging itself in the console wars Where they are up against sony, nintendo, and of course sharps new console which may cause a threat. ... This article or section does not cite its references or sources. ...

To clarify, the CLI is a specification, not an implementation, and is often confused with the Common Language Runtime (CLR), which contains aspects outside the scope of the specification. The Common Language Runtime (CLR) is the virtual machine component of Microsofts . ...

Among other things CLI specification describes the following four aspects:

The Common Type System (CTS) : A set of types and operations that are shared by all CTS-compliant programming languages.

Metadata 

Information about program structure is language-agnostic, so that it can be referenced between languages and tools, making it easy to work with code written in a language you are not using.

Common Language Specification (CLS) 

A set of base rules which any language targeting the CLI should conform to in order to interoperate with other CLS-compliant languages.

Virtual Execution System (VES) 

The VES loads and executes CLI-compatible programs, using the metadata to combine separately generated pieces of code at runtime.

All compatible languages compile to Common Intermediate Language (CIL), which is an intermediate language that is abstracted from the platform hardware. When the code is executed, the platform-specific VES will compile the CIL to the machine language according to the specific hardware. The Common Type System (CTS) is used by every language built on the . ... In computer science, a datatype or data type (often simply a type) is a name or label for a set of values and some operations which one can perform on that set of values. ... A programming language is an artificial language that can be used to control the behavior of a machine, particularly a computer. ... It has been suggested that Microsoft Intermediate Language be merged into this article or section. ... In computer science, an intermediate language is the language of an abstract machine designed to aid in the analysis of computer programs. ... A system of codes directly understandable by a computers CPU is termed this CPUs native or machine language. ...

Standardization and Licensing

In August 2000, Microsoft, Hewlett-Packard, Intel, and others worked to standardize CLI. By December 2001, it was ratified by the ECMA, with ISO standardization following in April of 2003. The Hewlett-Packard Company (NYSE: HPQ), commonly known as HP, is a very large, global company headquartered in Palo Alto, California, United States. ... Intel Corporation (NASDAQ: INTC, SEHK: 4335), founded in 1968 as Integrated Electronics Corporation, is an American multinational corporation that is best known for designing and manufacturing microprocessors and specialized integrated circuits. ... Ecma International is an international membership-based standards organization for information and communication systems. ... The International Organization for Standardization (ISO) is an international standard-setting body composed of representatives from national standards bodies. ...

While Microsoft and their partners hold patents for CLI, ECMA and ISO require that all patents essential to implementation be made available under "reasonable and non-discriminatory (RAND) terms." The companies have agreed, instead, to make the patents available under "royalty-free and otherwise RAND" terms. Reasonable and Non Discriminatory Licensing (RAND) is a term for a type of licensing typically used during standardisation processes. ...

Implementations

• Microsoft .NET Framework contains Microsoft's commercial implementation of the CLI for desktop systems, but also encompassing a larger collection of resources, libraries, and tools.
• Shared Source Common Language Infrastructure is a reference implementation of the CLI available from Microsoft, under the Shared source licensing program.
• .NET Compact Framework is Microsoft's commercial implementation of the CLI for portable devices.
• Mono development platform is a popular open source implementation of CLI and accompanying technologies, sponsored by Novell.
• Portable.NET, part of the dotGNU project, is another open-source implementation.

This article or section does not cite its references or sources. ... The Shared Source Common Language Infrastructure (SSCLI), previously codenamed Rotor, is Microsofts shared source implementation of the CLI, the core of . ... Shared source is a type of licensing program that allows controlled access to full or limited amounts of product source code. ... The Microsoft . ... Mono is a project led by Novell (formerly by Ximian) to create an ECMA standard compliant . ... Open source refers to projects that are open to the public and which draw on other projects that are freely available to the general public. ... Novell was also the name of a road bicycle racing team. ... DotGNU Portable . ... DotGNU is a part of the GNU Project that aims to provide a free software replacement for the Microsoft . ...

External links

• Tutorial including MSIL by Aleksey Nudelman

References

• Standard ECMA-335, Common Language Infrastructure (CLI). ECMA International. Retrieved on Aug 31, 2005.
• ISO/IEC 23271, Common Language Infrastructure. ISO. Retrieved on Sep 27, 2006.