If you are interested in building REST APIs on .NET in C#, you should look at the tutorials on http://www.asp.net/web-api http://www.asp.net/web-api or for MVC

If you are interested in building REST APIs on .NET in C#, you should look at the tutorials on http://www.asp.net/web-api http://www.asp.net/web-api or for MVC style web development try http://www.asp.net/mvc http://www.asp.net/mvc. With a free Azure account you can be up and running in no time with a working API. If you are interested in C# development for REST APIs that will run on Mono under Linux, then take a look at Nancy http://nancyfx.org/ http://nancyfx.org/ and ServiceStack https://servicestack.net/ https://servicestack.net/. P.S. ServiceStack v3 is open source and free. ServiceStack v4 is open source and requires a license.