[Magdalen] FaceBook question

[Grace Cangialosi]

Would someone who uses FB please tell me what a "Poke" is? A friend sent me a note this morning saying she had received a message saying she had been poked by me another friend. I told her I had no idea what that meant, but I'd try to find out.
The one I supposedly sent must have gone out by accident--kind of like one of those "butt dials" from a cell phone...