Dot Net (.net)

.NET is a programming framework.

Developers can use to create applications more easily. As comment-er  d wroth aptly put it, "a framework is just a bunch of code that the programmer can call without having to write it explicitly." In a perfect world, you wouldn't need .NET Framework.
How .net help programmers?
A Microsoft operating system platform that incorporates applications, a suite of tools and services and a change in the infrastructure of the company's Web strategy. The .NET Framework supports building and running of next gen of applications and XML Web services.

Main Principles Of .NET:

There are four main principles of .NET from the perspective of the user:
It erases the boundaries between applications and the Internet. Instead of interacting with an application or a single Web site, .NET will connect the user to an array of computers and services that will exchange and combine objects and data.
Software will be rented as a hosted service over the Internet instead of purchased on a store shelf. Essentially, the Internet will be housing all your applications and data.
How Net Works?
There will be new ways to interact with application data, such as speech and handwriting recognition.
Users will have access to their information on the Internet from any device, anytime, anywhere.