E-mail client
From Free net encyclopedia
An e-mail client (or mail user agent [MUA]) is a computer program that is used to read and send e-mail.
Originally, the MUA was intended to be just a little program to read the messages, which the MDA in conjunction with the MTA would transfer into a local mailbox.
The most important mailbox formats are mbox and Maildir. These rather simple protocols for locally storing e-mails make import, export and backup of mailfolders quite easy.
E-mails to be sent would be handed over to the MTA (perhaps via an MSA), therefore an MUA would not have to provide any transport-related functions.
Since the various Windows versions intended for home use never provided an MTA, most modern MUAs have to support protocols like POP3 and IMAP to comunicate with a remote MTA located at the e-mail providers machine.
IMAP and the updated IMAP4 are optimized for storage of e-mail on the server, while the POP3 protocol generally assumes that the e-mail is downloaded to the client. The SMTP protocol is used by most e-mail clients to send e-mail.
In addition to the fat client e-mail clients (or small MUAs in cooperation with a local MDA/MTA) presented here, there are also Web-based e-mail programs ("webmail").
An important standard supported by most e-mail clients is MIME, which is used to send binary attachments. Attachments are files that are not part of the e-mail proper, but are sent with the e-mail.
MAPI (Messaging Application Programming Interface) is a proprietary Microsoft Windows API which can be used to access the Microsoft Exchange e-mail server or to interact with the Microsoft Outlook client.
Javamail, part of the platform-independent Java API, can be used to develop e-mail clients or servers using any of the standard e-mail protocols.
See also
da:E-mail-klient de:E-Mail-Programm es:Cliente de correo electrónico fr:Client email ko:이메일 클라이언트 it:Client di posta nl:E-mailclient ja:メーラー pl:Mail User Agent ru:Почтовая программа sv:MUA