1. <software> A software source tree packaged for distribution; but see kit.

2. <messaging> A vague term encompassing mailing lists and Usenet newsgroups (but not BBS fora); any topic-oriented message channel with multiple recipients.

3. <messaging> An information-space domain (usually loosely correlated with geography) to which propagation of a Usenet message is restricted; a much-underused feature.

[Jargon File]