(pronounced as separate letters) Short for
Simple Mail Transfer Protocol, a
protocol for sending
e-mail messages between
servers. Most e-mail systems that send mail over the
Internet use SMTP to send messages from one server to another; the messages can then be retrieved with an
e-mail client using either
POP or
IMAP. In addition, SMTP is generally used to send messages from a mail client to a mail server. This is why you need to specify both the POP or IMAP server and the SMTP server when you
configure your e-mail
application.