Net-centric abbreviation for the popular exclamation "Oh my God!" (generally used in conversations to exclaim surprise or disgust). Most commonly used by teenage girls who find it depressingly hard to type out an entire word. Reinforces assumptions that humans seem to be getting dumber from generation to generation. See also u, like.
Teenage idiot: "like OMG did u c dat totaly cutte gy? he wuz like, so cutte"