Pen spinning is a form of object manipulation that involves the deft manipulation of a writing instrument with hands. Although it is often considered a form of self-entertainment (usually in a school or office setting), multinational competitions and meetings are sometimes held. It is sometimes classified as a form of contact juggling; however, some tricks, e.g. "spreads" and "aerial tricks" do leave contact with the body. Pen spinning has quickly gained international popularity through online video sharing and forums. The hobby has been popular around the world since at least the 1970s.