At university in NZ in 1975 when I conducted a trial I entered data on to a coding sheet, which which went to the office that ran the IBM mainframe. Someone put it on punch-cards and fed it into the computer. I got the results and the punch cards back a few days later. I guess I still have them stashed away somewhere.
It was several years before I had anything to do with a computer again. That included a couple of years living in a part of SE Asia where mains electricity and the nearest telephone were 20 km away.
My first hands on experience was on the original Mac in 1985, when I went back to university. They had just installed a lab full of them, and we were allowed a few hours a week on them for a basic computing course. I finished the course within about half the time allowed (and got my only ever A grade). I used the remaining time available to make spreadsheets modelling different scenarios for another course (in which I got a B+, not bad for a student who would normally happily settle for a C). We also learned to use IBM clones running MS DOS…. dunno why. I guess still have the now obsolete floppy discs I used then stashed away somewhere.
Again it was about a decade before I used a computer again, when I heard about "internet cafe's". I checked one out in Cambridge, England, and signed up with the Hotmail address I still use, and became a regular user of email as other folks I knew got on-line. A few years later, working at various places, I started to use Word and Photoshop a bit on office desktop computers….. all seemed a bit of hassle, having to install drivers for peripherals and not all that reliable though. At that stage a computer was a computer to me. I knew nothing of differences between operating systems, apps and so on.
The first computer I owned was the original Mac Mini in 2005. Living a somewhat itinerant life, I wanted something occasionally easily transportable, but I didn't (and still don't want) a portable. It was pleasing to discover that it was much easier to use, and more reliable than the Windows based machines I had been using…….