I remember having to use Borland Turbo pascal on DOS in college for a couple of courses. I was spoiled having done a ton in THINK Pascal (and THINK C) previously for my own software in high school. We actually had to have it open in class for a few pieces of work but otherwise I'd do all my work on my Mac in THINK Pascal and spend a little time "porting" it back to Turbo Pascal so it would run for my prof and TA. https://journal.paoloamoroso.com/rediscovering-turbo-pascal