Re:IBM, sonic delay lines, and the history of the 80×24 display
by int_19h on Wednesday February 14, 2024 @04:58PM
(#39376113)
IBM punch cards had 80 columns because that's how much they could cram onto the already-existing standard Hollerith punch card by making holes smaller and rectangular without making the cards too fragile.
Said standard punch card size was 3.25 by 7.375 inches, which not coincidentally is exactly the size of a 1887 dollar bill. The reason why that size became so common is because it was used in the 1890 US census, which was the first widely publicized application that popularized the technology. And the reason why it matches the size of the dollar bill is because Hollerith could then reuse cash storage boxes used by the US Department of Treasury for cards.
Said standard punch card size was 3.25 by 7.375 inches, which not coincidentally is exactly the size of a 1887 dollar bill. The reason why that size became so common is because it was used in the 1890 US census, which was the first widely publicized application that popularized the technology. And the reason why it matches the size of the dollar bill is because Hollerith could then reuse cash storage boxes used by the US Department of Treasury for cards.
(http://www.columbia.edu/cu/computinghistory/census-tabulator...)