Hollerith (or IBM) punch cards (top left), were used with the mainframe computers of the 1970s, both to input data and programs. Punch cards were 80 columns wide. At left are a few IBM Job Control Language (JCL) cards used to control programs running in "batch mode" on an IBM 370 mainframe.  

Before punch cards and computes, came McBee Keysort System cards (bottom). Libraries used McBees to check out books, and to perform inventories. 

The edges of the cards were notched, to indicate certain conditions, for example the due date of a book. A needle was passed through the holes at the proper point, and the deck dropped. The cards matching the desired conditions fell out.