WEB API 2 is a framework for building HTTP services that can be accessed from any client including browsers and mobile devices. It is an ideal platform for building RESTful applications on the .NET Framework.
HTTP is not just for serving up web pages. HTTP is also a powerful platform for building APIs that expose services and data. HTTP is simple, flexible, and ubiquitous. Almost any platform that you can think of has an HTTP library, so HTTP services can reach a broad range of clients, including browsers, mobile devices, and traditional desktop applications. ASP.NET Web API is a framework for building web APIs on top of the .NET Framework. The following are the return types for Web API action methods.