Background

Before we delve into the building blocks and design principles behind ASP.NET Web API, it is important to understand that ASP.NET Web API is an evolution of the existing continuous Microsoft efforts to enable support for HTTP Services. A timeline of events that describe this evolution are outlined next.

Windows Communication Foundation (WCF) (https://msdn.microsoft.com/en-us/library/ms731082%28v=vs.110%29.aspx) was launched with .NET 3.0 for SOAP-based services; the primary aim was to abstract the transport layer and enable support for the WS-* protocol. No HTTP features were enabled except HTTP POST for requests

In NET 3.5, WebHttpBinding (https://msdn.microsoft.com/en-us/library/system.servicemodel.webhttpbinding%28v=vs.110%29.aspx) was introduced in WCF with the intent to support services that were not based on SOAP. It allowed systems to configure endpoints for WCF services that are exposed through HTTP requests instead of SOAP messages. The implementation was very basic and...