Introduction of .Net Framework

The .net framework has two components:-

·         .Net Framework Class Library (FCL)

·         Common Language Runtime (CLR)

Before we start learn FCL and CLR lets learn about Common Language Specification (CLS). The Common specification (CLS) enforces that software development languages should be interoperable between them. the code written in a CLS should be compliant with the code written in another CLS Complaint language. Microsoft  .Net Framework support languages like Microsoft Visual Basic.Net, Microsoft Visual C#, Microsoft Visual C++ .Net and Microsoft Visual J# .Net.

The common language runtime is the foundation of the .Net Framework. CLR act as an agent that manages code at execution time providing core services such as memory management, thread management etc. while also enforcing strict type safety and facility with code accuracy that ensure security and robustness.

The class library, is an integral component of the .Net Framework, consists of object oriented collection of reusable classes (types) that we can use to develop application ranging from traditional command-line or any graphical user interface (GUI) application such as Window Forms. ASP.NET Web Forms and Windows Services the newly invented XML Web Services.

The Diagram below depicts in detail the .Net Framework structure.

History of .Net Framework

Microsoft started development of the .NET Framework in the late 1990s, originally under the name of Next Generation Windows Services (NGWS). By late 2000 the first beta versions of .NET 1.0 were released.

Version 3.0 of the .NET Framework is included with Windows Server 2008 and Windows Vista. Version 3.5 is included with Windows 7 and Windows Server 2008 R2, and can also be installed on Windows XP and Windows Server 2003. On 12 April 2010, .NET Framework 4 was released alongside Visual Studio 2010.

The .NET Framework family also includes two versions for mobile or embedded device use. A reduced version of the framework, the .NET Compact Framework, is available on Windows CE platforms, including Windows Mobile devices such as smart phones. Additionally, the .NET Micro Framework is targeted at severely resource-constrained devices.

Overview of .NET Framework release history
Generation	Version number	Release date	Development tool	Distributed with
1.0	1.0.3705.0	2002-02-13	Visual Studio .NET	N/A
1.1	1.1.4322.573	2003-04-24	Visual Studio .NET 2003	Windows Server 2003
2.0	2.0.50727.42	2005-11-07	Visual Studio 2005	Windows Server 2003 R2
3.0	3.0.4506.30	2006-11-06	Expression Blend	Windows Vista, Windows Server 2008
3.5	3.5.21022.8	2007-11-19	Visual Studio 2008	Windows 7, Windows Server 2008 R2
4.0	4.0.30319.1	2010-04-12	Visual Studio 2010	N/A
4.5	4.5.50709.17929	2012-08-15	Visual Studio 2012	Windows 8, Windows Server 2012