Email: Eliminate confusion between the concepts of «MAIL FROM» and «From»

Looking through various articles I was confused by different names of From-headers of email. Now I want to put all aliases of FROM and TO headers into one table.

First of all it is necessary to understand that email consists of two parts: «envelope» and «content». Quotation from RFC5322:

«In the context of electronic mail, messages are viewed as having an envelope and contents. The envelope contains whatever information is needed to accomplish transmission and delivery. (See [RFC5321] for a discussion of the envelope.)  The contents comprise the object to be delivered to the recipient.  This specification applies only to the format and some of the semantics of message contents.  It contains no specification of the information in the envelope.»

Each of parts contains its own FROM and TO headers/fields. In fact, there are many other headers (sender, cc, bcc and etc.), I will not consider them all, so read the RFC.

A content part consists of two sections: «header» and «body». Quotation from RFC5321:

«The SMTP content is sent in the SMTP DATA protocol unit and has two parts: the header section and the body. If the content conforms to other contemporary standards, the header section consists of a collection of header fields, each consisting of a header name, a colon, and data, structured as in the message format specification (RFC 5322 [4]); the body, if structured, is defined according to MIME (RFC 2045 [21]).»

For clarity, I presented the email format graphically (very primitively):

Here is a table with different names of fields FROM and TO. I think the most correct name with RFC (RFC5321.MailFrom, RFC5322.From and etc.).

Part	Command / format	Aliases
Envelope	MAIL FROM:<reverse-path> [SP <mail-parameters> ] <CRLF>	RFC5321.MailFrom Envelope from Envelope sender 5321.From 2821 FROM Return-Path Reverse path Bounce address Mfrom
	RCPT TO:<forward-path> [ SP <rcpt-parameters> ] <CRLF>	RFC5321.RcptTo Envelope recipient
Content Header section	"From:" mailbox-list CRLF	RFC5322.From Letter from Message from Header from 5322.From Friendly from
	"To:" address-list CRLF	RFC5322.To Letter to Message to Header to
	"Cc:" address-list CRLF	RFC5322.Cc Carbon Copy
	"Bcc:" [address-list / CFWS] CRLF	RFC5322.Bcc Blind Carbon Copy