The Origins of APL

1974 talk show style interview with the original developers of APL; complete with plaid jackets and a smoking host.

The Origins of APL Video

I've never used APL but I found the talk to be very interesting. They talk about how APL come about, its evolution and the character set. Worth watching.

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Thanks!! I have only watched

Thanks!! I have only watched the first ten minutes so far, but this is highly interesting.

Strange location to host

Strange location to host such treasures, I have to say.


If you look at the "Video Details" it also says how the interview came to be.

I also found the video from Kenneth Iverson's Memorial interesting. Lots of people reminiscing about him and his work.

Origins of APL

Funny topic to appear! I was a high school student in Chicago at the time and spent summers at SRA on Grand Ave. I got to meet Iverson a few times, once at SRA in Chicago (it was doing a lot of work and research into APL) and once at the Watson center.

I was involved in testing the APL/1130 and a little later on the IBM/360. I was also involved in the implementation on the IBM/1500 (no that isn't a mistake for 5100! There was actually another implementation).

When APL was running on the 360/91 it was being used by quite a few people and groups including some the engineers at NASA.

Not so funny... We love APL!

Not so funny... We love APL!

Don't get me wrong...

APL is a wonderful language though I was told it was more a religion! lol.

When I said funny I meant to find a video of Larry Breed, Ken Iverson and others that I spent a few summers in Yorktown and 67-69 at SRA in Chicago, in the evenings as a high school student.


Hello Chuck,

I am trying to resurrect APL\1130 from APL\1130 assembly decks rescued and available at the website. It appears that in order to assemble these source decks and generate a set of binary decks to - finally - generate an APL\1130 disk is quite special.

Do you have any recollections on how to assemble the APL\1130 source decks, particularly on the order of the assembly and how to generate the different binary decks (loader, etc.)?

Thanks in advance,



The total amount of hair on that panel is stupendous...

I salute them.

Thanks for the post

Dear Bashyal,

I'm not sure how you stumbled upon my posting of the Origins of APL, but I'm so glad you found it.

My name is Catherine Lathwell and my sister passed me this page today after one of her neighbours in Euclid, Ohio passed it to her. Our father was on the original APL implementation team and I believe was at a conference in Denmark for the team at the time The Origin's of APL was produced.

I am currently working on a documentary film about APL/J/K, here in Toronto, Canada. You can watch the film unfold at

Thanks again for the post. And don't you worry, I am working on finding a permanent and safe home for all these treasures.


This is totally excellent! Thanks for letting us know about the project. Best of luck, and I'm sure many of us will be interested to see the result!

Just serendipity

Hi Catherine,
I had started reading "A Programming Language" book and wanted to find more information about Kenneth Iverson so I did a search for "kenneth iverson video" and the first link took me to your video submissions page on myspace.

Very cool that you're working on creating such a documentary. Will definitely follow the website.

Up Date

It's a good time to give you folks an update.

You've sent a fine number of referrals to my site. And to think, I found you because my sister's neighbour in Ohio happened to mention this post the week before she came to Toronto to visit for Christmas! Lovely.

Anyway, here's where I am right now:
'Chasing men who Stare at array' status report AKA 'Bread, roses and women'

Paparazzi Me

I wish I could put photos here!

I bumped into Ken Iverson's son Eric Iverson on the street the other day. He does a pretty good job of keeping himself out of the spotlight, even though he is quite involved with J.

The thing of the thing is, when a woman you've know since she was two asks if she can post your photo in her blog, how can you say, no? Ha. You can't.

Paparazzi me!

Visit to IBM's Old Philadelphia Scientific Center Building

Hi Folks,

It's me again. You guys rock. I'm getting plenty of referrals from this site and it keeps me smiling for DAYS.

Thanks for following my under-dog project. You make me proud.

Rock on!

It Ain't No Taj Mahal