The act of lying face down on an object while remaining rigid much like a plank of wood. Often, a photograph is taken of this act and posted on social media outlets. Often performed by lying on objects which are either completely awkward or dangerous, such as a basketball hoop or the middle of a road. The origins of planking can be traced back to the "lying down game" which has its roots in Japanese Anime.
Kyle: "Mike, I'm going to go planking on that stop sign over there!"
Mike: ".... dude, you're a faggot, no I will not take a picture of you being a douche bag."
Kyle: "But I will get so many comments on this picture of Facebook!"