B.2. Email: Fetching and Managing Messages

The POP mechanism is defined in a long series of documents beginning with RFC918 (October 1984, Post Office Protocol) and culminating in RFC1939 (May 1996, Post Office Protocol - Version 3). There is also an obscure companion to RFC1081, RFC1082 (November 1988, Post Office Protocol - Version 3, Extended Service Offerings), that defines a way to use POP for group discussion, in a manner analogous to the IMAP public folder. The author of RFC1082 wrote:

Since mailers and user agents first crawled out of the primordial ARPAnet, the value of discussion groups have been appreciated (though their implementation has not always been understood).