Are maine coon cats the only cats with an "M" on thier forehead?

Im trying to figure out if maine coon cats are the only cats that have an "M" on thier forehead. I have a cat with an "M" on his head but I he's not a maine coon. Or at least I dont think that he is. He was a stray when I found him as a kitten. Please help or tell me when to go to get the answer.