• A newsgroup is a debate about a certain topic made composed of notes posted to a central Internet site and distributed over USENET, a global network of news discussion groups. The Network News Transfer Protocol (NNTP) is used by Usenet .
• Subject hierarchies are used to structure newsgroups, with the first few letters of the newsgroup name identifying the principal subject category and sub-categories denoted by a subtopic name. There are several layers of subtopics in many subjects. News, rec (recreation), soc(society), sci(science), comp(computers), and so on are some of the primary subject areas (there are many more). Users can establish new newsgroups, post to existing newsgroups, and respond to past posts.

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