Mail User Agent

(Computers) program that enables a user to compose and read email messages (serves as an interface between the user and the mail transfer agent), MUA

An e-mail client is a frontend computer program used to manage e-mail. Large all-in-one e-mail clients such as the open source Mozilla Thunderbird and Microsoft Outlook today combine the operations of an MSA, MDA, MRA and MUA in one application. However, MUAs like Mutt are also sometimes referred to as e-mail clients.
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<messaging> (MUA) The program that allows the user to compose and read electronic mail messages. The MUA provides the interface between the user and the Message Transfer Agent. Outgoing mail is eventually handed over to an MTA for delivery while the incoming messages are picked up from where the MTA left it (although MUA's running on single-user machines may pick up mail using POP).
Popular MUAs for Unix include elm, mush, pine, and RMAIL.
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(1996-03-21)