Difference between ASP.NET 2.0 and ASP.NET 3.5

what are the Difference between ASP.NET 2.0 and ASP.NET 3.5 | Multi Targeting in asp.net | what are the Asp.net 3.5 features

Here I will explain about differences between asp.net 2.0/3.0/3.5. Generally we will see the questions like difference between Asp.net 2.0, 3.0 and 3.5 but there is no Asp.net 3.0 version. We have a version of 3.0 .NET Framework.

Check below table for the differences between Asp.net 2.0 and Asp.net 3.5

SNo	Feature	Asp.net 2.0	Asp.net 3.5
1.	New Features	Asp.net 2.0 includes the following new features 1)    Master Pages 2)    Profiles 3)    Girdivew Control	Asp.net 3.5 includes the following new features 1)    Listview Control 2)    DataPager Control 3)    Nested Master Pages 4)    Linq DataSource
2.	Multi Targeting	Asp.net 2.0 does not support multi-targeting environment	Asp.net 3.5 supports multi –targeting What is multi – targeting? Check below description
3.	Ajax Support	There is no built-in support for AJAX in asp.net 2.0 , it has to be installed and downloaded	In Asp.net 3.5, Ajax is integrated in .NET framework, thereby making the process of building intuitive cool user interfaces easier
4.	Silverlight Support	It does not support for silverlight	It support for silverlight
5.	JavaScript Debugging	It does not support for JavaScript debugging	It support for JavaScript debugging
6.	LINQ Support	It doesn’t support LINQ	It supports LINQ

What is Multi-Targeting?

With the past few releases of Visual Studio, each Visual Studio release only supported a specific version of the .NET Framework.  For example, VS 2002 only worked with .NET 1.0, VS 2003 only worked with .NET 1.1, and VS 2005 only worked with .NET 2.0.

One of the big changes we are making starting with the VS 2008 release is to support what we call "Multi-Targeting" - which means that Visual Studio will now support targeting multiple versions of the .NET Framework, and developers will be able to start taking advantage of the new features Visual Studio provides without having to always upgrade their existing projects and deployed applications to use a new version of the .NET Framework library.

Now when you open an existing project or create a new one with VS 2008, you can pick which version of the .NET Framework to work with - and the IDE will update its compilers and feature-set to match this.  Among other things, this means that features, controls, projects, item-templates, and assembly references that don't work with that version of the framework will be hidden, and when you build your application you'll be able to take the compiled output and copy it onto a machine that only has an older version of the .NET Framework installed, and you'll know that the application will work.