There are now people old enough to read this who have only ever known a world where Internet access is just as taken for granted as electricity and tapwater. This wasn't always the case, even as recently as the nineteen nineties.
When the Internet was first opened up for commerce by the US government in nineteen ninety-two, the only way most people could access it was over the phone line. The phone line, being designed to let two people talk to one another, was ill equipped to carry digital information, so connections were very slow. Websites of the time largely consisted of text. Seldom even including their own styling information, most were just black serifed text set against the default light grey background of Mosaic and Netscape, with very few images. Even then, downloading a Web page took several seconds.
The device that hooked up your computer to the phone line, turning data into audible beeps and hisses, was called a modem. Going even further back to the eighties, most hackers hadn't yet heard of the Internet -- at the time, it was only used by the government and, reluctantly, universities. Hackers bought modems just to get their computers to directly talk to each other in their own neighbourhood.
Oblivious to what was becoming a global network of computers, there was a parallel community of tens of thousands of people who let others dial into their computers. These people were known as system operators, or sysops for short. Each ran software on his or her machine that turned it into a bulletin board system, or BBS for short, and each BBS had its own distinct community of dozens of local users who would leave messages for each other and share small files. Very small files.
Although most simply catered to their local town, some served a specific community. The Gay and Lesbian Information Bureau in Virginia, GLIB for short, helped gay and bisexual people realise they weren't alone, while Promises and The Homestead in Brentwood and Nashville, Tennessee, helped people recover from alcohol addiction.
Eventually, just as all communities generally tend to make the shift from chaos to order, BBSes started to phone each other up late at night when calls were cheap in order to swap their messages, forming FidoNet. This enabled people from all over America, and later the world, to exchange e-mails and public messages together as long as they didn't mind waiting for a few days while each BBS passed on its own messages to its neighbours, slowly pushing them outwards.
Anyone old enough to remember these BBSes probably cringes a little bit when someone too young to remember them refers to a forum on a website as a bulletin board system. Many hackers who were at least adolescents in the eighties remember how amazing it seemed to be able to share messages and files with a bunch of people in their area using just their computer, a modem and their phone line.
In technical terms, BBSes resembled the command prompt more than a website. They generally showed 80 columns by 25 rows of text, and primitive, blocky graphics using the ANSI X3.64 standard. They resembled teletext more than anything else.
In personal terms, they were a way for hackers to talk to each other, in much the same way as a tangible bulletin board in a town square lets people leave messages for all to see. BBSes were social places, much like modern web forums with the exception that you could hop on your bike and meet the people you were talking to because they generally lived in the same town.
It's kind of sad to realise just how few people these days even realise that these things ever existed.
Thankfully, Jason Scott maintains a website preserving the text files that were shared on BBSes, over at textfiles.com. While it is sort of interesting to browse, however, it doesn't get across the emotional investment people had in the various BBS communities that sprang up.
For just this reason, Scott also made a documentary about BBSes, called, appropriately enough, BBS: The Documentary. It explores many aspects of these communities, and the emotional impact they had on their participants. Anyone interested in this chapter of the history of hacker culture should check it out, as it covers this social phenomenon in commendable detail.