If you've done a standard Mandrake Linux installation, mail access servers (POP3 or IMAP) are launched on demand by the xinetd super daemon. When a connection is done on the POP port (or IMAP), the xinetd daemon launches the appropriate program to answer the request.

A POP3 user will fetch his e-mails on his computer and will read them with a mail reader like kMail or Evolution, while the IMAP protocol allows users to leave their mails on the server and manage it remotely. IMAP is really adapted for mobile users, but, because mails consume a lot of disk space, the system administrator should check regularly his server or set-up quota policies.