Going to "/Zoo/LookAtTheMonkey" means that you want to call the LookAtTheMonkey action inside the Zoo controller. If you look in your global.asax file, you will see the default route mapping defined in RegisterRoutes() which is "{controller}/{action}/{id}" with the "id" paramater being optional. The great thing about this is you can specify any type for the "id" parameter (if it has a string representation) like string/int/Guid/etc. when you create your action methods.

That site also appears to be quite old, but is still useful for teaching the MVC concepts.

If you are starting out on MVC, I would recommend using the razor view engine instead of the "aspx" view engine. It's got a much cleaner/nicer layout than "aspx" views.