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Next: Electronic Mail Functions Up: Lecture 5
Nature of Electronic Mail
Electronic mail is a messaging system modelled on postal mail that sends, receives and stores messages solely within electronic media.
Unlike faxes, the post and telegrams e-mail messages never need to be transcribed onto a physical medium.
Unlike the phone, e-mail is an asynchronous messaging service.
Unlike paging and SMS, e-mail is not for real-time messaging.
Electronic mail systems consist of
| user agents | let people read and send messages |
| message transfer agents | move messages from source to destination |
| mailboxes | store messages sent to recipients |
Typical user agents are command, GUI or web based programs.
Typical message transfer agents are daemons running on servers.
Typical mailboxes are files.
Typical e-mail systems support 5 basic functions
| composition | creation and addressing of messages and answers |
| display | enabling viewing/rendering of incoming messages |
| disposition | dealing with message upon receipt |
| reporting | telling originator what happened to message |
| transfer | movement of messages from originator to recipient |
| Lecture 5 | XHTML 1.0 | Slide 1 |