We got fidonet in Zimbabwe in the early 1990s. It was utterly revolutionary for us - more than the internet that came later really. For the first time we could communicate with my two brothers overseas without paying for extremely exorbitant international telephone calls that lasted a couple of minutes at best.
Our modem was 2400bps (8-N-1 IIRC). We used the zmodem protocol. It was after I learned about computers but I learned a HUGE amount from this about protocols etc. Our phone system was terrible so error correction etc were of great importance. Working out how to dial slowly was also important for our terrible phone exchanges.
It let me keep in touch with my pal, K, who emigrated to South Africa and as a result he ended up sending me 21 1.2MB floppy disks with SLS Linux on them and kernel 0.99 (I think). The journey began! :-)
İ developed a Netmail server for Hitnet called HitBase in 1995 or so. It allowed people to discover others around their city to meet. Possibly the earliest thing that resembles Facebook. Similarly, it was a privacy nightmare too, luckily short-lived.
HitNet introduced me to great people some of whom I still see today. It was such a tight-knit friendly community.
The advent of Internet killed it but some communities are still active on other platforms.
(previously all transfers, Xmodem/Ymodem, were one-way with CRC checks on each block slowing things down)
Whenever I hear about this new fangled AT protocol all the kids are jazzed about, I get all wistful for the BBS era.
FidoNet & PC-Relay were pretty fanfastic. For the time, obv.
Source: Was sysadmin for a hub.
An interesting aspect is that it was impossible to obtain an address without providing some service or newsletter on a specific subject to the sysop in return, so it was a privilege to have your own FidoNet address.
And yeah, Zmodem was mind-blowing for us.
What I miss most is the local community aspect. In my teens and early 20's I met several friends through BBSes.
[1] https://archive.org/details/20021102-bbs-herring/Mark+Herrin...
Later on of course some nodes started distributing over the Internet so setting up a node became much easier (and I think there was a way for the node to allow multiple users read/write without even setting up a node/point at all).