[6][needs update] Based on ASP.NET, ASP.NET MVC allows software developers to build a web application as a composition of three roles: Model, View and Controller.

A controller handles interactions and updates the model to reflect a change in state of the application, and then passes information to the view.

"[10] The ASP.NET MVC framework couples the models, views, and controllers using interface-based contracts, thereby allowing each component to be tested independently.

[citation needed] In March 2012, Scott Guthrie announced on his blog that Microsoft had released part of its web stack (including ASP.NET MVC, Razor and Web API) under an open source license (Apache License 2.0).

[11] Guthrie wrote that "Doing so will enable a more open development model where everyone in the community will be able to engage and provide feedback on code checkins, bug-fixes, new feature development, and build and test the products on a daily basis using the most up-to-date version of the source code and tests."