1. A selfie taken with two or more people. These are commonly taken through a mirror to fit more people in the shot.
2. Commonly used to look popular and give your Instagram, twitter, Facebook and myspace followers the impression that you have a life and lots of friends.
"Oh my god, lets take a group selfie for Instagram"
Justin: I want to take a selfie but I want to look like I'm popular
Selena: I'll take a group selfie with you.