Here’s a brief article about a favorite classroom example of mine. The 1890 US Census used tabulating machine technology developed by Herman Hollerith.
His company formed the foundation of IBM.
This article from Columbia University has some more background and this IBM page has the following image of an 1890 tabulator.

I keep a stack of Hollerith cards in my office, and sometimes I’ll bring these punch cards to class to show students how data was stored in the analog era.
Here’s a punch card from the 1960 US Census (image courtesy Universitaet Klagenfurt)


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