(1) (.NETwork) A top-level Internet domain used by carriers, ISPs and other communications-oriented organizations. See Internet domain name.

(2) (.NET) A comprehensive software development platform from Microsoft that was introduced in 2000 as the company's next generation programming environment. Pronounced "dot-net," and widely known as the ".NET Framework," it was designed to compete with the Java J2EE platform.

.NET and CLI
The European Computer Manufacturers Association (ECMA) has standardized .NET as the Common Language Infrastructure (CLI). ECMA also standardized the C# programming language, designed by Microsoft to be the flagship .NET language. Depending on the class libraries used, the output of .NET and CLI compilers may be identical or not.

Web Services and Component Software
Microsoft's .NET supports SOAP-based Web services and Microsoft's next generation component software, expected at a later date. In the interim, .NET supports Microsoft's COM component software model. Version 2.0 of .NET, introduced in 2005, incorporates the WinFX API, which is the programming interface included in Windows Vista.

The Heart of .NET/CLI
The heart of .NET/CLI is a cross platform language system. Similar to Java because it uses an intermediate bytecode language that can be executed on any hardware platform that has a runtime engine, it is also unlike Java, as it provides support for multiple programming languages.

.NET compilers generate Microsoft Intermediate Language (MSIL) bytecode, and CLI compilers generate Common Intermediate Language (CIL) bytecode. MSIL is executed by the Common Language Runtime (CLR), and CIL bytecode is executed by the Virtual Execution System (VES). Both the CLR and VES are runtime engines like the Java Virtual Machine (JVM) in Java (see Java Virtual Machine).

.NET Programming Languages
Microsoft provides several .NET languages, including C# (C Sharp), J# (J Sharp), Managed C++, JScript.NET and Visual Basic.NET. Numerous other languages have been reengineered as CLI languages as can be seen in the following diagram (see CLI). See CLR, .NET Enterprise Server and C#.

(NETwork) Any term with a "net" prefix either means network or Internet. For example, a net address can mean a network address or an Internet address, depending on the context of the dialog. "Net" with a capital "N" generally refers to the Internet; for example, "the Net" is "the Internet." See also .NET.

See CompTIA.