People read articles in newsgroups which have been posted by others.
People may respond to articles either publicly, by posting to the newsgroup or privately, via email to the author of the article. Articles are threaded and it is easy to follow the discussion of a particular topic, because the initial and subsequent postings are grouped together. To participate in the newsgroups, you need a news reader client. The client connects to a server over the Internet and downloads the current articles from a newsgroup and posts your responses. Many web browsers include a news client, just as they have an email program.