A keypunch machine is an early form of data entry device that was used to produce punched cards, which enabled users to input data into early computers. It consisted of a keyboard and a mechanism to punch holes in cards in corresponding positions, representing letters and numbers.
The use of keypunch machines declined rapidly in the 1960s and 1970s as computers became more sophisticated and affordable. With the introduction of magnetic tape and disk storage, punched cards became less common as a means of data storage, and newer input devices like the computer keyboard and mouse became more widely used. The advent of personal computers and the development of graphical user interfaces made it possible to input data directly into a computer, eliminating the need for keypunch machines.
When a key on the keyboard was pressed, a corresponding set of pins would punch holes into the card in a specific pattern, encoding the data. The punched cards could then be read by a computer, which would interpret the pattern of holes as data. Keypunch machines were used both to input data into mainframe computers and to store it for later processing.
See also: analog computer, computing machine