In the intro I liked the precursors to the IBM "Thinkpad" name.

9-track tape drives, drum disks, rectangular switches and lights, IBM "THINK" logo, fast card readers ... all bring back many personal memories.

This submission popping back up from the second chance pool got me to do some digging for the formal description of system/360[0], this is not the APL we know today but the APL outlined in Iverson's A Programming Language[1].

[0] https://www.cs.trinity.edu/~jhowland/class.files.cs2321.html...

[1] https://www.jsoftware.com/papers/APL.htm

I went to the Hampshire College Summer Studies in Mathematics in 1979, where we learned APL with all its glorious obscure characters and overstrikes. Lots of fun.

"The simple things are not obvious."

Truer words were never spoken.

I was fascinated with APL after picking up a book on it at a bargain store and so took an APL class in college. It wasn’t offered in my CS curriculum, it was in the Architecture curriculum.

For some more APL history see the "50 Years of APL" at the Dyalog URL

https://www.dyalog.com/50-years-of-apl.htm

My favorite quote from this video, that I wish more languages would embrace is:

"I went from application to application trying to use the same techniques. The most encouraging thing is that they would work. After 2-3 years during which time the language had grown by accretion, it grew and grew, eventually I found it was shrinking.

    Essentially the idea was once you look at enough different applications you begin to see what is the general notion. So I came to generalisations that allowed me to take out whole chunks of special things I had put in.

    Furthermore to my surprise it turns out the general ideas are usually much simpler to understand than any of the special cases."