The .NET Framework

The .NET Framework is a common environment for building, deploying, and running Web Services and Web Applications.

NET framework 2.0:

It brings a lot of evolution in class of the framework and refactor control including the support of:
Generics, Anonymous methods, Partial class, Nullable type..
The new API gives a fine grain control on the behavior of the runtime with regards to multithreading, memory allocation, assembly loading and more Full 64-bit support for both the x64 and the IA64 hardware platforms
New personalization features for ASP.NET, such as support for themes, skins and webparts.
.NET Micro Framework
New personalization features for ASP.NET, such as support for themes, skins and webparts.

.NET framework 3.0:

Also called WinFX,includes a new set of managed code APIs that are an integral part of Windows Vista and Windows Server 2008 operating systems and provides

Windows Presentation Foundation (WPF), formerly code-named Avalon; a new user interface subsystem and API based on XML and vector graphics, which will make use of 3D computer graphics hardware and Direct3D technologies.
• Windows Communication Foundation (WCF), formerly code-named Indigo; a service-oriented messaging system which allows programs to interoperate locally or remotely similar to web services.
• Windows Workflow Foundation (WWF) allows for building of task automation and integrated transactions using workflows.
• Windows CardSpace (WCS), formerly code-named InfoCard; a software component which securely stores a person's digital identities and provides a unified interface for choosing the identity for a particular transaction, such as logging in to a website.
Windows Communication Foundation (WCF), formerly called Indigo; a service-oriented messaging system which allows programs to interoperate locally or remotely similar to web services.
Windows Presentation Foundation (WPF), formerly called Avalon; a new user interface subsystem and API based on XML and vector graphics, which uses 3D computer graphics hardware and Direct3D technologies.
Windows Workflow Foundation (WF) allows for building of task automation and integrated transactions using workflows.
Windows CardSpace, formerly called InfoCard; a software component which securely stores a person's digital identities and provides a unified interface for choosing the identity for a particular transaction, such as logging in to a website

.NET framework 3.5:
It implement Linq evolution in language. So we have the folowing evolution in class:

Linq for SQL, XML, Dataset, Object Addin system, p2p base class, Active directory,
ASP.NET Ajax, Anonymous types with static type inference, Paging support for ADO.NET
ADO.NET synchronization API to synchronize local caches and server side datastores
Asynchronous network I/O API Support for HTTP pipelining and syndication feeds.
New System.CodeDom namespace.

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