According to Wikipedia, "Originally BBSes were accessed only over a phone line using a modem
, but by the early 1990s some BBSes allowed access via a Telnet, packet switched network, or packet radio connection. Early BBSes were often a local phenomenon, as one had to dial into a BBS with a phone line and would have to pay additional long distance charges for a BBS out of the local calling area. As the use of the Internet became more widespread in the mid to late 1990s, traditional BBSes rapidly faded in popularity. Today, Internet forums occupy much of the same social and technological space as BBSes did, and the term BBS is often used to refer to any online forum or message board."