What is the .NET framework?

-->The .NET framework is a collection of tools and utilities ,Its actually a  platform for building, deploying, and running Web services and applications.
-->The MS.NET framework includes the standard compilers (C#, VB.NET, J#, C++.NET, Jscript.NET), various utilities like (caspol, ngen, installutil, tlbimp, sn, asmreg, ildasm, etc), runtime environment (CLR) and Base Class Libraries.

Following are the core features of DotNet Framework   
          * Simplified Programming Model
          * Simplified Deployment
          * Programming Language Integration

Simplified Programming Model

All operating system services accessed through common object-oriented programming model (E.g.) File Access, Data Access, Threading and Graphics. 

Simplified Deployment

we can deploy a project just by few clicks.

Language Interoperability

The CLR allows different programming languages to share types.The CLR provides a Common Type System (CTS)

CTS is also a set of standards. CTS defines the basic data types that IL understands. Each .NET compliant language should map its data types to these standard data types. This makes it possible for the 2 languages to communicate with each other by passing/receiving parameters to/from each other. For example, CTS defines a type Int32, an integral data type of 32 bits (4 bytes) which is mapped by C# through int and VB.Net through its Integer data type,

The CLS is a specification that defines the rules to support language integration. This is done in such a way, that programs written in any language (.NET compliant) can interoperate with one another. This also can take full advantage of inheritance, polymorphism, exceptions, and other features.