To add a little more, in the mid-80's before Compuserve, AOL and the other online services for consumers were Internet-based, there was Usenet:
Usenet - Wikipedia, the free encyclopedia
I had Usenet access through our local Hewlett Packard office via UUCP using a dialup modem in our office. We also had some access through our local university while I was there.
Usenet newsgroups, some of which are still quite active, have some advantages over forums:
- Speed. Very important if you're reading and answering a lot (just ask mD

).
- Much lower bandwidth requirements. That's not as important now.
- You can choose your own reader (this is somewhat true using some of the mobile forum aggregators).
- Decentralized.
- Easier to subscribe to most... just find the newsgroup and join (unless it was private, then you needed a password).
P.S. Cabrio... sorry for bringing in the S.I... Cardinal Fang! Fetch...THE COMFY CHAIR!