Do WebApi 2 and MVC 5 user different routing attributes?

Question

Reading through this blog post on attribute routing in ASP.NET MVC 5 and this one on attribute routing in Web Api 2, it looks like there are two sets of routing attributes, one in the System.Web.Mvc namespace and the other in System.Web.Http.

1. Is that right and does anyone have any idea (links) as to why it was designed this way?
2. Should one be used over the other or are they supposed to live side by side?

Answer 1

1. Yes, these route attributes are intentionally different since Web API and MVC have distinct (but similar) routing systems
2. Use the MVC RouteAttribute on MVC controllers/actions. Use the Web API RouteATtribute (System.Web.Http) on Web API controllers/actions. If you use one that doesn't match, it likely just won't work.