Usenet is a worldwide distributed system of discussion groups in which millions of people participate. There are many Usenet groups and anyone on the Internet may participate for free. In other words, Usenet is a group of public forums for discussions.

Usenet was originally designed to carry local news between two universities in North Carolina. Therefore, Usenet groups are commonly referred to as Newsgroups also. Usenet is also called as ‘The News’ or ‘Netnews’. As in forums, in each newsgroup, people send messages, called articles, for other people to read. Once an article is sent to a group, anyone in the world may read it. Some newsgroups are ‘moderated’, in such newsgroups, the articles are first sent to a moderator for approval before they appear in the newsgroup.

Check out the image below. It describes the complete Usenet architecture. Click on the link for a bigger image.

A Usenet group name consists of two or more parts, separated by periods (Eg: news.newusers.questions) and they can be can be accessed via Outlook Express which comes along with Internet Explorer or on the web via Google.