One line of computer programming, whichever language you were using. Up to 80 characters wide, same as the card's width.

I remember. And we loved it. No home computers, no cellphones, no internet. Mid 70's in my case.


A nicer photo, showing a used card and details.

We can see the card's instruction, I highlighted in green :

Z(1) = Y + W(1)

In English, it takes a lot more wording to transmit the instruction, but I believe it would read as: "Let array Z, cell 1 be equal to variable Y plus contents of array W, cell 1"

...where Z and W were previously defined and initialized as single dimensional (think a straight line of mailboxes, each cell contains some value you chose to store there) arrays.

It's been a long time, Fortran. 😉

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@shibaprasad @Full_marx I forgot to mention the other highlighted box, on the right side of the card -- it was the project number, so if you dropped or mixed the card you could still find where it belonged.

Wasn't it lovely? 😄

@shibaprasad @Full_marx @hansw
After the mainframe and Fortran, punched cards time, my next experience was with an early home computer, a Sinclair Z80 clone, and it was not the best thing to type on.

Things change a lot, certainly. 😃

Guy Steele would like you show you his one-card wonder for the #IBM1130 - "the ugliest program I ever wrote" - with full disassembly and explanation.

@retrocomputing #retrocomputing
@design_RG @Full_marx


Thank you, Ed! I will add the video you linked to my ever growing Tabs list, to be processed.

I found a nice image showing how each of the possible characters was encoded into a card, it's here:

Some characters are one single punch hole (each character occupies one vertical column, out of the 80 possible in the card), some use two punch holes, which combined represent the character.

I was looking at images and found a nice one of the IBM Model 29 card punch, which is the one I personally worked with to create my first programmes in first year Uni classes. It was a solid, well built, last forever machine.

@retrocomputing @Full_marx

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