A newsgroup is an online discussion forum accessible through Usenet. Each newsgroup contains discussions about a specific topic, indicated in the newsgroup name. You can browse newsgroups and post or reply to topics using a newsreader program. Access to newsgroups also requires a Usenet subscription. Most Usenet providers offer monthly access for around $10 USD per month.
Newsgroups may be either moderated or unmoderated. In a moderated newsgroup, a moderator must approve posts in order for them to become part of the discussion. In an unmoderated group, everything posted is included in the discussion. Some newsgroups may also use bots to moderate the content, automatically eliminating posts that are deemed offensive or off topic.
While many people now use web forums and online chat instead of newsgroups, the service is still popular around the world. In fact, there are estimated to be over 100,000 newsgroups in existence. While many newsgroups host traditional text-based discussions, a large number of newsgroups are now used for file sharing. These newsgroups, which primarily provide links to files, often have the term "binaries" in their name.
Below are some examples of active newsgroups. The first part of the name (before the first dot) is the primary category (or hierarchy) or the newsgroup. For example, sci. is used for science-related discussions.
You can browse discussions and post to newsgroups using a newsreader.