Chad (paper) device which will not punch a complete circle in the tape but, instead, will only cut approximately three-quarters of the circumference of a circle ... thereby leaving a movable, or hinged, lid of paper in the tape." In the "New Hacker's Dictionary", two unattributed and likely humorous derivations for "chad" are offered, a back-formation from a personal name "Chadless" and an acronym for "Card Hole Aggregate Debris". Other etymologies claim derivation from the Scottish name for river gravel, "chad", or the British slang for louse, "chat". When a chad is not fully detached, it is described by various terms corresponding
Hole punch has a long lever which is used to push a bladed cylinder, the punch, straight through one or more sheets of paper and then through a close fitting hole in the die. As the vertical travel distance of the cylinder is only a few millimeters, it can be positioned within a centimeter of the lever fulcrum. For low volume hole punches, the resulting lever need not be more than for sufficient force. Two paper guides are needed to line up the paper: one opposite where the paper is inserted, to set the margin distance, and one on an adjacent side.