programming languages
Bill Gates and DONKEY.BAS
It's hard to imagine now, but in the early days of Microsoft, Bill Gates was an actual programmer [https://blog.codinghorror.com/how-to-become-a-better-programmer-by-not-programming/]. One bit of hard evidence is the BASIC program DONKEY.BAS [http://en.wikipedia.org/wiki/DONKEY.BAS] included with original IBM PCs running IBM