The Journey of the Email, Literally.

The concept of email and its daily use in our lives has changed the way the world operates in the last 50 years, whether business or personal. It is instantaneous and free to send, but what goes on underneath and how does electronic mail actually send out instantly?

The Origin of email
According to Darwin Magazine, the first email message was sent in 1971 by Ray Tomlinson, to himself. His eventual breakthrough was being able to send messages to other machines on the Internet using the @ sign to determine the receiving end. And for those who love to deconstruct and reconstruct in order to find out how all the pieces fit together, I’ve summarized the journey your email takes after it leaves your computer. It’s amazing all that entails within a few seconds of hitting the send button!

Sender to Recipient
As soon as you hit send, your email transmits through the mail server which transmits your message along with the list of intended recipients. This message is transmitted with Simple Mail Transfer Protocol (SMTP), which is a language used to speak to the mail server. This server where your email departs on its journey is popularly known as the Outgoing SMTP Server.

The SMTP server will then process the recipient’s email domain address, the part that identifies where to send the mail to. If you send an email to me at it is going to identify my domain ( and route to my domain’s server communicating with the DNS, or Domain Name Server. But it cannot deliver your message to me based on the Domain alone, it also needs your IP address. An IP address is a fingerprint that is assigned to every computer connected to the Internet. It will also check the receiving domain if they have any MX or mail exchange servers. This would be the equivalent of the Postmaster verifying the location on a map and checking to see if the recipient has a mailbox or P.O Box to receive your mail. By analyzing the domain and IP combination it now knows which SMTP server to connect with and is on its way to its final destination.

The receiving server is known as an MTA, or Mail Transfer Agent. It transfers the mail to the MDA or Mail Delivery Agent which stores the email and waits for the recipient to open it. Additionally MTAs are scanning for authenticity of your sending domain and content scans by spam filters. (Like an xray machine!) Think of an MTA as a sorting facility for mail and MDA as a mailbox to store messages. In order to access the email software is required such as an ISP or email client (such as Yahoo, Gmail, Microsoft Outlook, etc.) A great way to ensure that you pass through these “scanners & detectors” much like going through security at airports, is to authenticate your sending domain. Authenticating is a great way to inform the mail client that you are sending from an authorized domain and have it configured as well as implementing best sending practices. These two combinations will protect your mail reputation and give you much better chances of continuously landing in your subscriber’s inboxes. 🙂

In the midst of an MTA handing off the email to an MDA it uses 1 of 2 protocols to retrieve email:

  1. POP – This is used for retrieving email and in some cases leaving a copy of it on the server.
  2. IMAP – This is used for coordinating status of emails (opened, deleted, etc.) across multiple email clients.  With a copy of every message saved on the server.

The acronyms tend to portray the inner workings of electronic mail as difficult, but once you understand each acronym the process becomes easy to learn.

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