This is a list of newsgroups that are significant for their popularity or their position in Usenet history.

As of October 2002, there are about 100,000 Usenet newsgroups, of which approximately a fifth are active. This number varies, depending on the news server carrying the newsgroups.

The Big 8 hierarchies

These are the most widely distributed and carefully controlled newsgroup hierarchies. See Big 8 (Usenet) and the Great Renaming for more information.

comp

Computer-related topics.

humanities

Topics related to the humanities (fine arts, literature, philosophy, etc.).

misc

Miscellaneous topics.

• misc.taxes.moderated ? A moderated professional tax forum open to the general public

news

Matters related to the functioning of Usenet itself.

• news.admin.net-abuse.blocklisting — discussion related to the use of blocklists to deal with spam and other unwanted network traffic.
• news.admin.net-abuse.email — discussion of abuse of email by spammers and other parties.

rec

Recreation and entertainment topics.

• rec.arts.sf.tv.babylon5.moderated — discussion of Babylon 5 and other projects of J. Michael Straczynski.
• rec.arts.tv.soaps.cbs ? discussion about soap operas broadcast by the CBS television network.
• rec.arts.tv.mst3k.misc — discussion of the TV series Mystery Science Theater 3000.
• rec.humor.oracle — Internet humor
• rec.sport.cricket — general discussion of world cricket.
• rec.sport.soccer — general discussion of world football (soccer).
• rec.woodworking — general discussion of woodworking.

sci

Science-related topics.

soc

Discussion related to society and social subcultures.

talk

Discussion of various topics, especially controversial ones.

• talk.bizarre — a newsgroup for experiencing the bizarre.
• talk.origins — evolution-creationism controversy which maintains an extensive FAQ.

The alt hierarchy

This is the most extensive newsgroup hierarchy outside of the Big 8.

• alt.2600 — Official group for 2600: The Hacker Quarterly
• Alt.Adoption — for adoption
• alt.arts.poetry.comments — for poetry and poetry critique
• alt.atheism — discusses atheism
• alt.binaries.slack — artwork created by and for the Church of the SubGenius.
• alt.callahans — Spider Robinson's Callahan's Place online
• alt.config — creation of new newsgroups in the alt.* hierarchy.
• alt.digitiser — discussion of the video games magazine Digitiser.
• alt.fan — fandom discussions.
• alt.gothic — a gothic newsgroup and birthplace of Convergence
• alt.horology This Internet newsgroup concerns all aspects of horology (the science of time and timekeeping, clocks and watches). Those posting to it range from novices to collectors to professional watchmakers & clockmakers.
• alt.religion.kibology — He who Greps.
• alt.religion.scientology — discussion of the controversial subject of Scientology.
• alt.sex — the first alt.* newsgroup for discussion of sexual topics.
• alt.sex.bondage — discussion of BDSM sex.
• alt.sex.cancel — set up specifically as a means of defeating newsgroup spam cross-posted to the entire alt.sex hierarchy
• alt.sex.stories — text-based erotic stories of all types.
• alt.slack — Posting relating to the Church of the Subgenius.
• alt.suicide.holiday — pro-choice discussion of suicide.
• alt.sysadmin.recovery — the Scary Devil Monastery.
• alt.tasteless — discussion of subject matter in too poor taste to be discussed elsewhere.
• alt.tv.simpsons — discusses the TV show The Simpsons.
• alt.usenet.kooks — discussion of Usenet kooks and their idiosyncratic theories.
• alt.zines — discussion of small-press publications, magazines, and pamphlets (zines).

Other newsgroups

These newsgroups fall outside of the official Big 8 hierarchies, as well as the less formal alt hierarchy.