ASP.NET MVC 3
- New Project Templates having support for HTML 5 and CSS 3.
- Improved Model validation.
- Razor View Engine introduced with a bundle of new features.
- Having support for Multiple View Engines i.e. Web Forms view engine, Razor or open source.
- Controller improvements like ViewBag property and ActionResults Types etc.
- Improved Dependency Injection with new IDependencyResolver.
- Partial page output caching.
ASP.NET MVC 4
- ASP.NET Web API, a framework that simplifies the creation of HTTP services and serving a wide range of clients.
- Adaptive rendering and other look-n-feel improvements to Default Project Templates.
- A truly Empty Project Template.
- Based on jQuery Mobile, new Mobile Project Template introduced.
- Support for adding controller to other project folders also.
- Task Support for Asynchronous Controllers.
- Controlling Bundling and Magnification through web.config.
- Support for OAuth and OpenID logins using DotNetOpenAuth library.
- Support for Windows Azure SDK 1.6 and new releases.
ASP.NET MVC 5:
- Bootstrap replaced the default MVC template.
- ASP.NET Identity for authentication and identity management.
- Authentication Filters for authenticating user by custom or third-party authentication provider.
- With the help of Filter overrides, we can now override filters on a method or controller.
- Attribute Routing is now integrated into MVC 5.