Wikipedia
WWIV
WWIV was a popular brand of bulletin board system software from the late 1980s through the mid-1990s. The modifiable source code allowed a sysop to customize the main BBS program for their particular needs and aesthetics. WWIV also allowed tens of thousands of BBSes to link together, forming a worldwide proprietary computer network, the WWIVnet, similar to FidoNet, but with fewer problems related to forum management.