Electronic mail is the use of a network to transmit text messages, memos, and reports. Users can send a message to one or more individual users, to a predefined group, or to all users on the system. When you receive a message, you can read, print, forward, answer, or delete it. Not only are there different applications used to send and receive email such as MS Mail, VAX Mail, Eudora, Pine mail etc.
EMail is very fast.
A message you send from one side of the world can arrive at the other side in a matter of minutes under the right conditions. Also, if a file exists on your computer you can normally send it as email either by copying the contents of the file into your mail message or by attaching the file to the message as an attachment or enclosure. Currently, the principal problem is one of security. The method used to transmit information across networks in not yet secure. Perhaps in the near future a method of security will be implemented but until then it is the responsibility of each user to make their message secure by using encryption programs.