Message summary
E-mail messages consist of two parts:
- Message header
- Message body
- The fields of the message header are
RFC2822specified in this LINK - Minimum header field required
Date:andFrom: only. - A blank line separates the message header from the message body.
Header field’s
Date:
- Represents the time when message transmission started.
- Required field.
From: / Sender: / Reply-To:
- From: Sender: Represents the author of the message and S represents the sender of the message.
- From: Is a required field.
- Sender: Fields should not be used if the author and sender of the message are the same .
In the case where these fields are used properly RFC2822, the example in which the creator of the message delegates the transmission to the secretary is given.
- Reply-To: Is what the author of the message suggests as a reply destination.
To: / Cc: / Bcc:
Familiar, that specified in the mail client.
- Bcc: For messages where fields are defined RFC2822, specifies one of the following implementations:
- Bcc: Remove the field
To:/Cc:/Bcc:in sending the same message to all specified destinations. - To: The same message with the field deleted is sent to
Cc:the destination specified by andBcc: . Bcc:If there are three recipients, A, B, and C,Bcc:B and C are removed from the fields of the message sent to A. Bcc:Send as a message with an empty field with no defined value .
By the way, To: it seems that it is not an essential field. It’s not intuitive because most email clients can’t send unless you specify this.
Subject:
- Familiar, that is displayed as “subject” in the mail client. RFC2822Then, in the same section
Comments: / Keywords:is specified , but it seems that it is not used much, so I skipped it.
Return-Path: / Received:
As for these fields, “ RFC2821Look”, so take a look at on THIS link. However, I gave up this time because it seemed that I could not understand it without studying mail relay.
