I go way back:

My first computer experience was at work, ca. 1979. I got a login on a corporate UNIX network. No PC's then: a dumb terminal with a modem linked to a DEC PDP11 "minicomputer" (which was the size of two large refrigerators and was kept in air conditioned space in a corporate computer center). Not long after, we got connected to something called "DECnet," which was a nationwide network of users who were hosted on DEC minicomputers. It was a predecessor of the Internet. No GUI--you just logged into DECnet, selected a usergroup, posted a question or comment, and waited for a reply. It was a great experience in those days. I logged into a usergroup on bicycles and asked about a certain bike frame. Within an hour I got four erudite replies.

DECnet proved so popular that the company disconnected us from it because too many people were spending too much time on it, and not enough on what the company was paying them for.