1. A packaging of the Linux kernel (core) with various user interfaces, utilities, drivers, and other software into a user deliverable. Often available as a free download or in a low-cost CD-ROM package. Popular distributions include Caldera OpenLinux, CoreLinux, Debian, Red Hat, Slackware, SuSE, TurboLinux and others. From I-gloss

2. n. 1. A software source tree packaged for distribution; but see kit. Since about 1996 unqualified use of this term often implies `Linux distribution'. The short for distro is often used for this sense. 2. A vague term encompassing mailing lists and Usenet newsgroups (but not BBS fora); 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-underutilized feature. From Jargon Dictionary