The incorrect grammatical term used widely on the internet. The easiest way you can spot someone say this is to get onto youtube, go to a video, and go to a controversial and popular comment/joke, and one of the comments will be an inconsiderate jerk either taking the comment too seriously, or not understanding the joke, then replying to the comment in ALL CAPS and forgetting about apostrophes.
Person 1: "What do you give an armless child for Christmas?
Nothing, he wouldn’t be able to open it anyways."
Person 2 "OMG WHERE ON YOUTUBE BE MORE NICER IDIOT"
This term is used to call someone a mistake because on the British M1 motorway an accident is a daily thing so in tern if you say to someone they where born on the M1 you are calling them an accident
Mike: fight me You: you where born on the M1
Mike falls to the ground in pain
kathy: "where you at on the map?"
George: "I've been out here"
Kathy: "I feel it"
Notice how George said "I've been out here", this suggests that he has been hoeing around and he is most likely talking to someone. Kathy should move on to the next person.