I think people missed the point of this thread?

The OP wants to know the singers who are famous enough to be known only by their first name. I mean, yes lots of singers only use one name, but what singers can you say like "britney" and you instantly recognise it as Britney Spears.
Britney is the best example of them all.
Best Singles of 2013 (March/April) My Twitter
1. Avril Lavigne - Here's to Never Growing Up
2. Paramore - Still Into You
3. Demi Lovato - Heart Attack
4. Selena Gomez - Come and Get It
5. Rihanna - Stay