6 Mar
2009
6 Mar
'09
12:28 a.m.
M H Stein wrote:
IBM did indeed patent the rectangular holes used in their 80 column
cards. Whether the brass roller was a major factor is questionable;
after all, their competitors also used punched cards.
But there's no question that the general acceptance of IBM's card
format and their locked-in customers were instrumental in IBM
becoming the giant that they did; while their competitiors struggled
during and after the depression, punch card sales helped IBM survive
and grow. As late as the mid-fifties punch card sales represented
30% of IBM's bottom line; see:
http://www.cbi.umn.edu/hostedpublications/pdf/IBMRochesterHistory.pdf
OK, now I'm reminded of library-checkout punched cards from the 60's.
They were around the same size as the card-catalog cards so as to fit in the
same pocket in the front of the book. The funny thing about them was they
were punched along the edges with some combination of rectangular notches and
round holes, IIRC.