A mail header is a block of text at the beginning of an email that contains information about the email, such as the sender, recipient, date, and subject. Checking the mail header can be useful for a variety of reasons, including verifying the sender’s identity, tracking the path of an email, and troubleshooting email delivery problems.
There are a few different ways to check the mail header of an email. One way is to use an email client or webmail service. Most email clients and webmail services allow you to view the mail header by clicking on the “View headers” or “Show original” option in the email message. Another way to check the mail header is to use a command-line tool such as `telnet` or `netcat`.
