E-mail (short for electronic mail) is a simple system designed to allow the sending and receiving of messages across a network. There have been e-mail systems in use in small computer networks for a long time. E-mail was one of the earliest services available on the Internet, having been invented in 1972 by Ray Tomlinson to send messages across the early distributed networks.
E-mail today, probably the widest used of all Internet services, is still used primarily for sending messages, but an increasing percentage of E-mail messages now include many additional features such as file attachment, forwarding, and message organization.
Receiving E-mail
Each E-mail program has a special way of displaying all of the incoming messages. A list of the messages are shown by who sent each message, either double-clicking on one or selecting the Open option will display the message. The layout of the message will match the layout of a newly created message with the message header information (To:, From:, Cc:, and Attachments:) and the Message Body.
Replying to a Received E-Mail
E-mail programs allow you to reply to a message you received by creating a new E-mail form but with certain areas filled out. The E-mail address of the sender is automatically placed on the To: line as well as your E-mail address on the From: line. Some programs even take the original message and place it at the top of the new Message Body.
Most E-mail systems allow you to forward the entire message you received to another E-mail address by selecting the Forward option. You can also add your own message to a forwarded E-mail.
Attachments
Another option is to attach a file to the E-mail message. Any text file can be sent with a message. Many E-mail programs allow more than one file to be attached. When selected, they are listed on the Attachments: line. (Note: It is always a good idea to tell the receiver in the message what kind of file you are sending and which program created it. It would create a real problem if the receiver could not open and use the attachment you sent.)
Saving Attachments
Files attached to incoming E-mail can be saved on the user's computer by clicking on the name of the attachment or choosing the Save Attachment option. The user will need to tell the E-mail program where to save the attachment.
Old Messages
Many E-mail services keep the already-read messages for a specific period of time before automatically deleting them. Because the amount of E-mail could be very large, an E-mail system is set up to purge itself of old E-mail. In order to keep a copy of an E-mail, the user needs to save a copy of it onto their computer's hard drive.