Client-Server Mail Protocols FAQ
A brief summary of POP3, SMTP, and IMAP, including pointers to sources and frequently-asked-questions sites.
Email Addressing FAQ
The user+box@host addressing FAQ. A discussion of what exactly is permissible and verifiable in an e-mail address.
Internet Mail Consortium
Information about IMC and its members, all the Internet mail standards, and links to several IMC-hosted mailing lists.
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.
Message Access Paradigms and Protocols
Provides background and compares the Post Office Protocol (POP) with the Internet Message Access Protocol (IMAP).
RFC822 Email Address Validator
Online service to check if an email address follows the syntax laid down in RFC822.
Recursive collection of search statistics of a single search criterion within a hierarchy of IMAP folders
An example of email statistics collection relying on IMAP protocol - by Switzernet.com