Older Than the Internet
Email is older than the Internet itself. As soon as computers learned to serve many users at once in the early 1960s, people wanted to leave each other messages, and a notable implementation arrived with MIT's CTSS project in 1965, letting users of the same machine write to one another.
The leap to messages between different computers came in 1971, when Ray Tomlinson sent the first network email over ARPANET, the Internet's ancestor. To separate the user's name from the machine's name, he reached for a neglected key and introduced the now-familiar syntax with the @ symbol. Every address on Earth still carries his choice.
The vocabulary and plumbing settled soon after: the term "electronic mail" dates to 1975, and SMTP, the protocol that still shuttles messages around the world, was implemented on ARPANET in 1983.
A Postal System Made of Servers
Email works on a store-and-forward model, which is a fancy way of saying it behaves like a postal system. Mail servers accept, forward, deliver, and store messages, and crucially, neither you nor the person you are writing to needs to be online at the same time. The message simply waits.
Your address encodes the whole route. The part before the @ is the local part, naming the mailbox, and the part after is the domain name, telling the world which mail system to knock on.
When you finally connect, your device typically talks to a mail server or opens a webmail interface to send or receive messages. Protocols like IMAP let your phone and laptop peek into the same mailbox, which is why reading a message on one device marks it read on the other.
From Plain Text to Attachments
The original email could carry words and nothing else. Internet email began as a communications medium restricted to ASCII text, the basic English-centric character set, with no images, no accents, and certainly no attachments.
The upgrade came through MIME, a set of extensions that taught email to carry expanded character sets and multimedia content such as images. Every photo you have ever emailed rode on that standard.
The globalization of the address itself has moved more slowly. International email, with internationalized addresses written in UTF-8 so that they can use non-Latin scripts, has been standardized but is still not widely adopted. Even the word itself needed settling: after years of "e-mail" versus "email", the unhyphenated spelling is now the standard form recommended by style guides and the IETF.
Buried in the Inbox
The scale of email is staggering. By 2011 there were approximately 1.4 billion email users worldwide sending 50 billion legitimate messages every day, and an email address is now treated as a basic requirement for business, government, education, and daily life in most countries.
Work runs on it. A 2010 study of workplace communication found that 83 percent of US knowledge workers felt email was critical to their success and productivity.
The dark side scaled just as fast. By 2003, up to 30 percent of all email traffic was spam, prompting laws like the CAN-SPAM Act, and the flood never receded: the percentage of spam email in 2021 was estimated at 85 percent of all traffic. Add legitimate mail on top and you get the modern condition the article calls information overload, the inbox that never empties.
