Usenet is a world-wide distributed discussion system. It consists of a set of "newsgroups" with names that are classified hierarchically by subject. "Articles" or "messages" are "posted" to these newsgroups by people on computers with the appropriate software -- these articles are then broadcast to other interconnected computer systems via a wide variety of networks. Some newsgroups are "moderated"; in these newsgroups, the articles are first sent to a moderator for approval before appearing in the newsgroup. Usenet is available on a wide variety of computer systems and networks, but the bulk of modern Usenet traffic is transported over either the Internet or UUCP.
WHY IS USENET SO
HARD TO DEFINE?
The first thing to understand about Usenet is that it is widely
misunderstood. Every day on Usenet, the "blind men and the elephant"
phenomenon is evident, in spades. In my opinion, more flame wars
arise because of a lack of understanding of the nature of Usenet
than from any other source. And consider that such flame wars arise,
of necessity, among people who are on Usenet. Imagine, then, how
poorly understood Usenet must be by those outside! Any essay on the
nature of Usenet cannot ignore the erroneous impressions held by
many Usenet users. Therefore, this article will treat falsehoods
first. Keep reading for truth. (Beauty, alas, is outside the scope
of this article.)
WHAT USENET IS?
Usenet is the set of people who exchange articles tagged with one or
more universally-recognized labels, called "newsgroups" (or "groups"
for short). There is often confusion about the precise set of
newsgroups that constitute Usenet; one commonly accepted definition
is that it consists of newsgroups listed in the periodic "List of
Active Newsgroups" postings which appear regularly in
news.lists.misc and other newsgroups. A broader definition of Usenet
would include the newsgroups listed in the article "Alternative
Newsgroup Hierarchies" (frequently posted to news.lists.misc).
An even broader definition includes even newsgroups that are
restricted to specific geographic regions or organizations. Each
Usenet site makes its own decisions about the set of groups
available to its users; this set differs from site to site. (Note
that the correct term is "newsgroups"; they are not called areas,
bases, boards, bboards, conferences, round tables, SIGs, echoes,
rooms or usergroups! Nor, as noted above, are they part of the
Internet, though they may reach your site over it. Furthermore, the
people who run the news systems are called news administrators, not
sysops. If you want to be understood, be accurate.)