How Email Looks

Your email reader application assembles a message into the format necessary for Internet transmission. If your network uses a different protocol system (or a different email system), the message might pass through one or more email gateways that convert the message into the Internet-ready format described in this hour. An email message sent over the Internet consists of two parts:

  • The header

  • The body

Like the body of the message, the header is transmitted as ASCII-based text. The header consists of a series of keyword field names followed by one or more comma-separated values. Most of the mail header fields are familiar to anyone who has worked with email. Some of the important header fields are given in Table 18.1.

Table 18.1. ...

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