Message Headers

An email consists of three vital components: the envelope, the header(s), and the body of the message. The envelope is something that an email user will never see since it is part of the internal process by which an email is routed. The body is the part that we always see as it is the actual content of the message contained in the email. The header(s), the third component of an email, is perhaps a little more difficult to explain, though it is arguably the most interesting part of an email.