System 3 - Definition

A System 3 punch card. Click to enlarge.

The IBM System/3 was a low-end business computer introduced in the early 1970s and aimed at new customers and organizations that still used IBM 1400 series computers or unit record equipment. It featured a new punch card format that was smaller and stored 96 characters. Instead of the rectangular punches in the classic IBM card, the new cards had tiny (1 mm), circular holes much like paper tape. Data was stored in six-bit binary-coded decimal code, with three rows of 32 characters each, or 8-bit EBCDIC, with the two extra holes located in the top rows. IBM System/370s with a proper card reader could also process the new cards.

For mass storage, the System/3 used a single-platter cartridge disk, roughly the size of a medium pizza.