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Let's take a quick look at how software was built in the MS-DOS era: Borland Pascal 7.
(raduzaharia.medium.com)
Discussions on vintage and retrocomputing
Yup, mine, too. I don't remember which version it was, but I'm pretty sure it was still "Turbo" (not "Borland") Pascal, in the late 1990s. Grade 10 computer science was taught on Macintosh QuickBasic and then grades 11 and 12 were "real" programming in Turbo Pascal.