Don't ask me why, but it really is Usenet, not Newsnet!
I currently have no news-access, therefore this info might be a bit outdated. In order to use Usenet, you need access to a newsserver. Some providers include a newsserver in their services, some don't. Usenet News is transmitted via Network News Transfer/Transport Protocol (NNTP).
-> There are alternatives if your provider doesn't supply one.
http://www.eternal-september.org/ allow free reading and posting after registration. Most of Debian mail lists gatewayed to linux.debian.* Usenet hierarchy. Keeps history for about half year.
https://news.aioe.org/ allow free reading and limited number of posting per IP per day. Most of Debian mail lists gatewayed to linux.debian.* Usenet hierarchy. Keeps history for about 3 months.
Gmane.org is NNTP gateway to mail lists. It allow posting to most of Debian mail list under gmane.linux.debian.* hierarchy (because they do not usually require subscription to post). As of 2016-08 after huge DDOS author decided to shut down the service.
- [Somewhat controversially] Google Groups (because it encourages top-posting and rich HTML formatting and disallow anonymous access, you should login to their service)
A (historic) list of public access news servers http://dmoztools.net/Computers/Usenet/Public_News_Servers/
The provider also selects which lists are offered. Not every server provides every newsgroup; especially, binaries groups are often not carried. Newsgroups are sorted by topic, and good newsclients will give you a way to search the available groups for keywords.
Some time ago, I was reading the debian-user mailing list via news. Note that you can't post to those gateway-newsgroups with a newsclient.
-> The Usenet gateway linux.debian.* will let you read debian-* via Newsreader. Theoretically, registering with bofh.it will allow you to post via the gateway. Alternatively, some (all?) Newsreaders will allow you to send mail from the Newsreader, and the Debian lists are set up to accept mail from anyone regardless of whether they're subscribed to the list or not.
slrn - character/curses/slang based. Highly configurable, supports killfiles via scoring.
- Gnus - emacs based, highly configurable, supports killfiling via sophisticated scoring mechanisms.
Mozilla (?SeaMonkey) - still, after more than a decade, no killfile functionality!
Alpine - is a rewrite of the PINE Message System that adds support for Unicode and other features. Works surprising well with gmane.org / aioe.org / lore.kernel.org.
tin - A console based newsreader
NNTP Server Software
- linux.debian.* - gateways to firstname.lastname@example.org
There are tens of thousands of topic specific lists in Usenet. Some hierarchies (sci, comp, news, ...) are controlled, whereas the alt.* hierarchy is chaos incarnate.
The Swen virus ("News" backwards) scrapes Usenet for email addresses then Spams those addresses. Posting to Usenet using an unmunged email address is a surefire way to get your email address added to Spammers' mailing list databases.
Of course, this is also a surefire way to dig Spammers out of their hideyholes, using their infrastructure, so you can hunt them down and kill them (... their accounts, of course).
Some newsgroups are moderated; you have to prove you're a real person to a moderator (or other entity) before your posts will be considered to be accepted.
Trolls and Usenet Kooks haunt Usenet (for what reason, no-one knows). Ignore them, killfile them, don't encourage them (as if they need any encouragement).
Much like Internet Relay Chat (IRC), Usenet has a long tradition with many customs peculiar to itself. Not learning and abiding by those traditions is a surefire way to get added to a killfile. Read the newsgroup FAQ, and lurk (read without posting) for a bit before attempting to post.
- Don't feed the trolls.
Except in Microsoft related newsgroups, don't toppost or bottompost and do attribute the author of the post to which you're replying (this means you, Google Groups!). Ensure you leave a little of the author's post in your reply to provide context for the remarks you're posting in reply.
- Don't post HTML.
Don't multipost (the same post, posted individually in multiple newsgroups). Crossposting (posting once, simultaneously, to multiple newsgroups) is acceptable, but ensure that replies are directed to a specific newsgroup, not all of them. If you don't yet know what any of this means, then don't try. Lurk is always a good thing to do until you understand the mores and customs of the inhabitants.
.sig files (~/.signature, appended to the bottom of posts) are, by tradition, four lines long or less.
- "One of the lessons of history is that nothing is often a good thing to do and always a clever thing to say." --Will Durant