Headers take data every time the message is sent and received. This means that messages that have gone back and forth can contain extremely long headers, as information is added each time it is sent, received, sent back, received again, and so on. There are several entries that are likely to be of the most interest to the average user. Reading these gives you a run down of where the email was sent and how long it took. This can be useful for dealing with connection issues or for determining where an email originated from.  Delivered-To: This is the address that the email was sent to. Received: This shows the IP address that received the email message (the recipient's email service) as well as the time. Return-Path: This is the address that sent the message. Message-ID: Shows a unique number to identify the message. From, Subject, To: This is the information entered by the sender. It shows the sender's name, the email subject line, and the recipient's name.

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Write a summary of the previous text in Vietnamese:
Hiểu cách thành lập các tiêu đề. Đọc các thông tin cơ bản.