Ken Shirriff did an in-depth write-up of the punched card sorter:
Punched card sorters were a key part of data processing from 1890 until the 1970s, used for accounting, inventory, payroll and many other tasks. This article looks inside sorters, showing the fascinating electromechanical and vacuum tube circuits used for data processing in the pre-computer era and beyond.
More details at Ken Shirriff’s blog.
Check out the video after the break.
I’m old enough that I started programming with punched cards …. each card had a sequence number in the last few characters.
A friend once lost her thesis (a box of cards) of the back of her motor scooter on a wet day. She retrieved the cards from various puddles, took them home, ironed them, the ran them thru the card sorter (by sequence number – you had to do it N times for N digits) then had the computer print out a new deck