While schools had Apple computers, many 40 somethings first cut our teeth with computers at home on the C64 or Vic-20. With the C64, I first saw a modem (300 baud) and connect to a BBS system, a floppy disk drive (5.25" - holepunched to use both sides), and compressed digital music (at a C64 club meeting someone had a 10 second snippet of compressed, digital music on a C64 - sounded like crap and took (the usual) 2 minutes to load, but it was a decade ahead of MP3s.)
It also had BASIC programming capabilities with the disk drives for storage. You could draw sprites/graphics, program songs, do basic word processing, etc. Save it on your floppy disk and you were set.
Finally, the C64 had great games that made the pre-NES home consoles like the Atari 2600 look like garbage. The game selection was big enough to where a lot of good games were eventually produced: Ultima III/IV/V (or Bard's Tale, Temple of Apshai, Sword of Fargoal) = World of Warcraft. Arcade/Adventure/Pinball Construction Kit(s) = Minecraft. Karateka/Yie Ar Kung Fu = every fighter game ever. Beachhead = a 2D Call of Duty. Other great games off the top of my head -- Mission Impossible, Raid Over Moscow, Summer/Winter Games (Epyx), Raid on Bungeling Bay, etc.
It was also our first exposure to pirated software trading and beating DRM (Fast Hack'Em, etc.). To play our pirated version of archon (a great cross of chess and 2-D shooter):
The system is a fossil today, but it was great for its time... You just kinda had to be there.