Usenet

Explanation: Hierarchical organized discussion forums. You read or post into these forums using a newsreader or a web-browser, that supports Usenet Newsgroups. Newsgroups do not only contain text, but can also contain binary files, which need to be decoded . You also need a server to connect to, in order to get the newsgroups. Note that different newsservers do not always carry the same (number of) newsgroups. Reference: How to use the Usenet Newsgroups