Client-Server Mail Protocols FAQ
- A brief summary of POP3, SMTP, and IMAP, including pointers to sources and frequently-asked-questions sites.
- http://www.faqs.org/faqs/mail/mailclient-faq/

MIME Meta-FAQ
- comp.mail.mime meta-FAQ: Help for MIME problems. Pointers to information about Multipurpose Internet Mail Extensions and some answers to common problems with MIME.
- http://www.faqs.org/faqs/mail/mime-faq/mime0/

The IMAP Connection
- University of Washington collection of IMAP documentation and resources.
- http://www.imap.org

Email Addressing FAQ
- The user+box@host addressing FAQ. A discussion of what exactly is permissible and verifiable in an e-mail address.
- http://faqs.org/faqs/mail/addressing/

Message Access Paradigms and Protocols
- Provides extensive background and compares the Post Office Protocol (POP) with the Internet Message Access Protocol (IMAP).
- ftp://ftp.cac.washington.edu/mail/imap.vs.pop

Internet Mail Consortium
- Information about IMC and its members, all the Internet mail standards, and links to several IMC-hosted mailing lists.
- http://www.imc.org/