Usenet is a collection of newsgroups. Newsgroups are online forums in which people discuss thousands of different topics. Each topic has its own newsgroup, and many topics are divided into sub-groups.
People post articles to the newsgroups, which anyone with access to the group can read.
Other people then post replies to the article. Some of that kind of news is certainly available. A newsgroup is a specific forum within a usenet list. Newsgroups are grouped into 'hierarchies' that subdivide groups for specific interests. Be aware that while most newsgroups allow the posting of articles, some only allow responses to posted threads, and some do not allow postings, and are for reading only.