Where did email come from? A brief history
Email predates the internet. Programmers at MIT added a MAIL command to a shared computer in 1965, and in 1971 Ray Tomlinson at BBN sent the first message between computers on ARPANET, choosing the @ sign to separate user from host. The standards that still carry mail today date from 1982. Free web mail arrived with Hotmail in 1996, and Gmail's 1 GB in 2004 taught a generation never to delete anything. Today about 4.5 billion people use email, and Radicati projects roughly 392 billion messages a day in 2026.
Inbox Scrub · October 4, 2026 · 6 min read
In this article
Before the internet: 1965
The first email system did not cross a network. It ran on one computer. In the summer of 1965, Tom Van Vleck and Noel Morris wrote a MAIL command for MIT's Compatible Time-Sharing System, which let the people sharing that machine leave messages in each other's files. It went into service that August. (Van Vleck)
That is the idea email still rests on: a message is a file delivered to someone else's mailbox, waiting until they look.
The @ sign: 1971
In late 1971, Ray Tomlinson, an engineer at the research firm BBN, combined two programs. One, SNDMSG, delivered local mail. The other, CPYNET, copied files between computers on ARPANET, the research network that became the internet. Together they sent a message from one machine to another. To address it, he needed a character that separated a person from the computer they used, and he picked @. (Internet Hall of Fame)
It caught on quickly. By 1973, the Computer History Museum notes, email was well over half of all ARPANET traffic. (CHM) The network had been built for sharing computing power. People used it mostly to write to each other.
The first spam: 1978
On May 3, 1978, Gary Thuerk, a marketer at Digital Equipment Corporation, sent an invitation to a product demonstration to 397 ARPANET accounts. (Guinness World Records) The Computer History Museum describes the reaction as swift and highly negative. (CHM)
The word came later. "Spam," from the Monty Python sketch in which the word drowns out everything else, was online slang by the late 1980s. It entered general use in 1994, when two lawyers posted an advertisement for immigration services to thousands of Usenet discussion groups at once. (Brad Templeton)
The standards: 1977 to 1992
Mail between different systems needs agreed formats, and the internet's are written down as RFCs, short for Requests for Comments.
| Year | Standard | What it did |
|---|---|---|
| 1977 | RFC 733 | First widely used format for message headers: From, To, Subject, Date. |
| 1982 | RFC 821 | SMTP, Jon Postel's protocol for moving mail between servers. Still the backbone. |
| 1982 | RFC 822 | The message format that replaced RFC 733. |
| 1984 | RFC 918 | POP, for downloading mail from a server to your own computer. |
| 1988 | RFC 1064 | IMAP, Mark Crispin's protocol for reading mail that stays on the server. |
| 1992 | RFC 1341 | MIME, which made attachments, images, and non-English text possible. |
These have been revised since. SMTP and the message format were updated in 2008 as RFC 5321 and RFC 5322, and IMAP most recently in 2021 as RFC 9051. But a mail server from 1982 and one from today would recognise each other.
The difference between POP and IMAP matters more than it sounds. POP moved mail off the server and onto your computer. IMAP left it on the server, synced to every device. IMAP won, which is why a mailbox today lives in one place, belongs to a provider, and counts against that provider's storage limit.
Email goes to the public: 1979 to 1997
Until the late 1970s, email belonged to universities, labs, and companies. CompuServe brought it to home computer owners from 1979. (WOSU) In the 1990s AOL made it a household habit, with a recorded voice announcing "You've got mail." Elwood Edwards recorded those words in 1989 for $200. (ABC News) We cover that story in the rise and fall of AOL email.
Those services charged for access. The next shift made the mailbox free and put it in a browser. Hotmail launched on July 4, 1996. (Microsoft) By the end of 1997 it had more than 9 million members, and Microsoft bought it. (Microsoft) Yahoo agreed to acquire Four11, the owner of RocketMail, in October 1997, and Yahoo Mail was built on it. (SEC filing) A free address no longer depended on who sold you internet access, and it could follow you when you changed providers.
Gmail and the end of deleting: 2004
Google announced Gmail on April 1, 2004, with 1 GB of free storage. (Google) Free accounts elsewhere at the time held a few megabytes and had to be emptied constantly. Gmail offered far more, plus search good enough that you never had to file anything.
The message was clear: don't delete, archive. For a decade that was good advice. It is also why a twenty-year-old Gmail account now holds tens of thousands of newsletters nobody will read again, and why the free 15 GB that Gmail now shares with Google Drive and Photos fills up. (Google One)
Gmail passed 1 billion monthly users in 2016. (TechCrunch) In January 2026, Google said 3 billion people rely on it. (Google)
Email in your pocket: 1999 to 2007
Research In Motion released the BlackBerry 850 in 1999, a two-way pager that pushed office email to the device as it arrived. (IEEE ComSoc) For most of the next decade, mobile email meant a BlackBerry and a corporate server.
Apple's iPhone, announced in January 2007, brought what Apple called desktop-class email to consumers: full HTML messages over POP and IMAP, and push mail from Yahoo at no charge. (Apple) Mail became something people checked dozens of times a day, and senders noticed.
The long fight with spam: 2003 to now
As free mail grew, so did spam. In the United States, the CAN-SPAM Act was signed on December 16, 2003. (White House archive) It did not ban unsolicited commercial mail. It required senders to identify themselves and to honour opt-out requests.
The more effective work was technical. Three standards let a receiving server check that mail really came from the domain it claims:
- SPF lists which servers may send for a domain. (RFC 7208)
- DKIM adds a cryptographic signature to each message. (RFC 6376)
- DMARC tells receivers what to do when those checks fail. It was published in 2015 (RFC 7489) and became a proposed internet standard in 2026. (RFC 9989)
In October 2023, Google and Yahoo announced that from February 2024, anyone sending more than 5,000 messages a day to their users must authenticate with these standards, offer one-click unsubscribe, and keep complaint rates low. (Google, Yahoo) Microsoft applied similar rules to Outlook.com from May 2025. (Microsoft) The one-click unsubscribe they require is itself a standard, RFC 8058, from 2017. It is why the Unsubscribe link at the top of a marketing email in Gmail usually works without opening a web page.
Where email stands in 2026
| Measure | Figure | Source |
|---|---|---|
| Email users worldwide | About 4.5 billion (2024) | Radicati |
| Emails sent and received per day | About 392.5 billion (2026) | Radicati |
| Share of email that is spam | About 45 percent (2025) | Kaspersky |
| Gmail users | 3 billion (company claim) |
Sixty years on, the model has hardly changed: a message is a file left in someone's mailbox. What changed is the volume. Most of what arrives now is legitimate but unwanted: receipts, newsletters, and notifications from companies you once gave an address to. Spam filters do not touch it, because you technically signed up. Clearing it means unsubscribing and deleting sender by sender, and that is the job Inbox Scrub does for a Gmail account. If you are choosing where to keep your mail in the first place, see the most used email providers in 2026.
Questions people ask
- Who invented email?
- No single person. Tom Van Vleck and Noel Morris wrote a MAIL command for MIT's time-sharing system in 1965, for users of the same machine. Ray Tomlinson sent the first networked email between computers on ARPANET in 1971 and introduced the @ sign.
- Why does email use the @ sign?
- Ray Tomlinson needed a character to separate a user's name from the name of their computer, and @ was on the keyboard, read naturally as "at," and did not appear in names.
- When was the first spam email sent?
- On May 3, 1978, when Gary Thuerk of Digital Equipment Corporation sent a product announcement to 397 ARPANET accounts. The reaction was immediately negative.
- How many emails are sent each day?
- The Radicati Group projects about 392.5 billion emails sent and received per day in 2026, up from 361.6 billion in 2024. Kaspersky estimates that about 45 percent of all email sent in 2025 was spam.