What is .Net?

In short we can easily explain .Net as in the following:
DotNet

What's New in .NET4.5?

There are many new services, features and updates in .NET 4.5, in terms of these following contexts:
New in NET
.NET 4.5 is designed to support these fundamentals, these also can be defined as framework or structural parts of .NET 4.5, these are as follows:

Developer Productivity

Developer Productivity is enhanced for directly supporting the future features of several structural parts and parts related to the Common Language Runtime (CLR). Outlines of developer productivity are:

Application Performance

Application performance is improved for several add-on functionalities to the developers. This modification in application performance will also increase the user experience in designing and developing. Some of those add-on functionalities are:

Continuous Innovation

Continuous innovation is supported by updating in the .NET Framework, JIT compiler, structure and many more services, that professional developers really require, whenever they talk about any modifications in the Microsoft .NET Framework. This continuous innovation is followed by these guidelines in .NET4.5:
Further details will be in my next article about .NET 4.5.