contains an Internet email address for a human user who controls the requesting user agent.
Quick facts
Description
contains an Internet email address for a human user who controls the requesting user agent.
Syntax
From: webmaster@example.com
Frequently asked questions
contains an Internet email address for a human user who controls the requesting user agent.
It is classified as a request header and can appear in requests or responses depending on context.
Sources & standards
Updated 2026-08-18