A domain is only half the battle actually. So unless Vimeo allows you to make your own personal website, you only have a name for your nonexistent website. Think of it like (it is a car analogy) having a title for a car. The title is the URL you purchase. The car is the actual place where you put your shit. The title directs people to you and your car. The URL is just an easier way to get to an IP address. For example:
216.86.148.10 is the same as
http://somethingawful.comThat URL is appended to that IP address. 216.86.148.10 is the literal address of the server that SA put all their stuff on.