Web development is a common development scenario which requires its own techniques and patterns. Since web development in many server technologies is strongly correlated with some stuff, like web server properties or client request details, then software developers had to find a way to reduce these dependencies. Regarding the above introduction, you would know why?

The reason is the isolation. We have to reduce these dependencies to improve the isolation level. So what was the solution? The solution was the introduction of new development patterns including Model View Controller (MVC). The most famous technology that is designed for MVC pattern is Ruby on Rails and one of its amazing popularity reasons is from here.

This evolvement in web development technologies forced Microsoft to think about an adaption of this pattern for its ASP.NET technology and the result was the introduction of ASP.NET MVC framework.

So in a nutshell:

·         Unit testing is great (and in my opinion is a mandatory part of development for today's software)!

·         Unit testing requires a high level of abstraction and isolation between different units of the application.

·         Unit testing also requires that you reduce the dependencies between your built-in platform objects to be able to create and raise them independently.

·         Traditional ASP.NET web form applications had some strong dependencies between some objects like HttpContext, HttpRequest and HttpRequest.

·         Microsoft had to adapt MVC for its web development technology.

·         Microsoft had to reduce all those dependencies and improve the isolation level.

·         So Microsoft had to build ASP.NET MVC pattern with new considerations for isolation and abstraction.

So ASP.NET MVC framework comes with new designs for some main ASP.NET classes like HttpContext, HttpResponse or HttpRequest and of course, follows MVC pattern.