.Net and C# release history

.Net Version Release history

.Net Version	Release Date	Tool	Feature
1.0	2002	Visual Studio .Net	First release of .net
1.1	2003	Visual Studio 2003	Support for ASP.Net mobile controls Supports side-by-side execution Security Changes
2.0	2005	Visual Studio 2005	Generics (with generic collection) Nullable Types Support of IPv6 addresses in .net remoting Common Language Runtime 2.0
3.0	2006	–	WCF (Communication framework) WPF (Presentation framework) WF (Workflow Foundation)
3.5	2008	Visual Studio 2008	LINQ Addin / Plugin Model (System.AddIn.Contract.dll)
4.0	2010	Visual Studio 2010	Parallel Computing Code Contracts Lazy Initialization Dynamic Language Runtime In-process side-by-side hosting Background garbage collection Covariance and Contravariance Common Language Runtime 4.0
4.5	2012	Visual Studio 2012	Enhanced regular expression support Default culture for application domain Zip compression Support of array with size more than 2GB Asynchronous file operation Improvement in parallel computing
4.5.1	2013	Visual Studio 2013	Ability to collect diagnostics information Ability to explicitly compact the large object heap (LOH) during garbage collection Additional performance improvements such as ASP.NET app suspension Multi-core JIT improvements

Note:
- .Net 3.5, 3.0 and 2.0 uses same common language runtime version 2.0.
- .Net 4.5, 4.5.1 and 4.0 share same common language runtime version 4.0.
- I have not included language features in above list e.g. Partial classes / anonymous method. I will cover them in following section.

C# Language Release history

C# Version	Release Date	Tool	Feature
1.0	2002	Visual Studio .Net	First release of .net
2.0	2005	Visual Studio 2005	Partial classes Support for generics Iterators Nullable syntax Anonymous methods Static class Volatile keyword
3.0	2008	Visual Studio 2008	Implicitly Typed Local Variables Extension Methods Lambda Expressions Type Inference Object and Collection Initializers Anonymous Types Automatically Implemented Properties Expression Trees
4.0	2010	Visual Studio 2010	Support for Covariance and Contravariance Optional parameters and named arguments Support for Dynamic and DLR Enhanced support for COM interop
5.0	2012	Visual Studio 2012	Async / Await Feature Support for caller information