Punched card available, e.g. "80-column card". A sequence of cards that is input to or output from some step in an application's processing is called a "card deck" or simply "deck". The rectangular, round, or oval bits of paper punched out were called chad ("chads") or "chips" (in IBM usage). Sequential card columns allocated for a specific use, such as names, addresses, multi-digit numbers, etc., are known as a "field". The first card of a group of cards, containing fixed or indicative information for that group, is known as a "master card". Cards that are not master cards are "detail cards". The
Knockout punch the easiest to use and can make holes up to in diameter. It is a two piece system where the dies are attached to the ram which is connected to the hydraulic unit via a flexible hose. There are several sizing systems for these punches. The two most common are those sized for standard electrical knockout sizes and those that are for true dimensional holes. A 3/4 inch conduit size punch actually punches a hole that is approximately 1.1 inches diameter for 3/4 nominal size conduit. A dimensional size punch makes a hole very close to the indicated size. Punch