Served as both input, output and storage system in the eary days!
Using Punch Cards by Bubbles Whiting (2016)
Source. Interview at the The Centre for Computing History.Once Upon A Punched Card by IBM (1964)
Source. Goes on and on a bit too long. But cool still.The 1890 US Census and the history of punchcard computing by Stand-up Maths (2020)
Source. It was basically a counting machine! Shows a reconstruction at the Computer History Museum.