mail server

program which responds automatically to requests sent by electronic mail

A mail transfer agent or MTA (also called a mail transport agent, message transfer agent, mail server, SMTPD (short for SMTP daemon), or a mail exchanger (MX) in the context of the Domain Name System) is a computer program or software agent that transfers electronic mail messages from one computer to another.
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1. <tool, messaging> A program that distributes files or information in response to requests sent via electronic mail. Examples on the Internet include Almanac and netlib. Mail servers are also used on Bitnet.
In the days before Internet access was widespread and UUCP mail links were common, mail servers could be used to provide remote services which might now be provided via FTP or WWW.
2. (Or "mail hub") A computer used to store and/or forward electronic mail.
(1995-05-05)