The name of the group was Community Memory, and according to an handout they distributed, the terminal was "a communication system which allows people to make contact with each other on the basis of mutually expressed interests, without having to cede judgment to third parties."Steven Levy, Hackers (Community Memory was established in August 1973)
Cheap long distance communication is one of the things that people like about the Internet. But it does much more than that.
Communicating on the Internet allows you reach people in ways that you just couldn't do otherwise. I work for a volunteer Internet group called Virtual Moreland. One day, someone wanted to find a particular person in America. He knew this person's name, that they worked in the alternative energy industry and that he once lived in a city in California. For two hours, we searched the Internet for some trace of this bloke, with no luck.
So, having exhausted our own resources, we talked to a group of people. We asked an alternative energy discussion group if anyone knew this man. Within 24 hours, we had a reply that told us his current business, his address and his contact details. That is the way that the Internet really works.
Some Web pages that you go to also have discussion groups attached to them. With some notable exceptions (see PhotoNet, http://www.photo.net/), these discussion groups are a failure. Usually, you find that hardly anyone has contributed to them.
This is mainly because you have to visit the Web page to participate in the discussion. Most people won't do that. It is too much effort for too little reward.
Sometimes, though, Web based discussion systems do generate enough steam to be interesting and useful. If you are interested in photography, I suggest that you visit PhotoNet and look at the question and answer discussion pages there. It is a very clever system, which takes into account how people really work on the Internet. And it works.