Mail Message  Format

When an e mail  is sent from one person  to another  a header containing peripheral information precedes  the body  of the message itself. This contained  information is contained in a series of header lines. The header liens and  the body of the message are separated by a blank line. Each header line contains readable ext consisting of a keyword followed  by  a colon  followed by value. some  of the  keyword  are required and others  are optional. Every header  must have  a from header line and  a to header line  a header may include a subject header line as  well as other  optional header liens  a message header looks like this.

The to field  gives the  address  of the primary recipient. Having multiple recipients is also  allowed. The  cc field gives  the addresses of any secondary recipients. In  terms  of  delivery  there is  o distinction  between  the primary and secondary recipients. The  terms cc ( carbon copy0 is a bit dated  since computers do not use cardoon paper but it is well established. The  Bcc( Billed carbon copy) field is like the cc field except that this  line  is deleted from all the copies  sent to the primary and secondary recipients. This feature  allows people  to send copies to third parties without the primary and  secondary recipients knowing this. The next two  field from and sender tell who wrote and sent  the message  respectively. A line containing  received is added by each message transfer agent along  the way. The  lien contains the agents identify the date and  data and time the message was received and other  information that can be used for finding  bugs in the routing  systems. The return path field is added  by the final message  transfer agent and was intended to tell how to get back  to  the sender.