The Justin Bieber female fan base worldwide is smiling today. There's not a new song or not a new video that has surfaced online ... It's something much bigger than that. He brought back his famous side swept hairstyle that made girls swoon at every glimpse they got of the singer.

Bieber premiered the familiar look on Thursday (Jan. 12) when he appeared in Las Vegas for the International Consumer Electronics Show to help unveil the TOSY mROBO Robot. But his new look stole the show -- and even annoyed a robot creator -- as photographers snapped away to deliver the first look at his new 'do.

So why the sudden change back to his old hairstyle? Could it have something to do with his girlfriend, Selena Gomez, who also debuted blue tips this week?

Whatever the reason for Bieber's new look, he made plenty of people happy all around the world with just one simple decision to his beloved hair!