1. A software source tree packaged for distribution but see kit. 2. A vague term encompassing mailing lists and Usenetnewsgroups (but not BBSfora) any topIC-oriented message channel with multiple recipients. 3. An information-space domain (usually loosely correlated with geography) to whICh propagation of a Usenet message is restrICted a much-underused feature. [Jargon File]