Microsoft .NET Framework - what is it?
The .NET Framework is a Microsoft technology that provides features and functions that can be used by programs which run under Microsoft Windows. It provides extra functionality that is not included in the basic operating system. Programs that take advantage of the latest Microsoft technology require the Microsoft .NET Framework to be installed, or they will not work. To run these new applications, you must ensure that an appropriate version of the .NET runtime is installed on your computer. If you are using Microsoft Internet Explorer, this page can tell you which versions of the .NET runtime are currently installed.
Many of the benefits of the .NET Framework are benefits for the software developer, so you may not think that there is any advantage to running .NET Framework based applications as a user. However, .NET applications do have some advantages for the end user. The program code is "managed" so that it cannot crash the computer or make it less stable. And program installation is simpler, so software conflicts and problems caused by missing or incorrect components should occur less often than with old-style Windows applications.
Applications that use the .NET Framework are able to exploit the latest features and technology, and are assured of being compatible with current and future versions of Windows. By installing the .NET Framework runtime on your computer you will be updating it to include technologies that will be part of the next version of Windows.
.NET Framework versions
An application may be written to use one of several different versions of the .NET Framework. These versions are backwards compatible. An application that requires .NET Framework 1.1 or 1.0 will run if .NET Framework 2.0 is installed on the computer (though it will use version 1.1 if that is also present.) .NET Framework 3.0 supersedes .NET Framework 2.0 and so on.
.NET Framework 1.1
This is the first version of the .NET Framework. It is present on all new computers supplied with Windows XP SP2, and may have been installed on other computers as an update.
.NET Framework 2.0
This is the second version of the .NET Framework. It is available as an update for computers running Windows XP and Windows Server 2003.
.NET Framework 3.0
This is the third version of the .NET Framework. It is effectively .NET Framework 2.0 with some extra features. It is installed as part of Windows Vista and is available as an update for Windows XP SP2 and Windows Server 2003.
.NET Framework 3.5
This is the latest version of the .NET Framework. It is available as an update for Windows XP and Windows Vista and will be included in Windows 7.