Ray Tomlinson, the American programmer widely credited as the inventor of email, died Saturday morning. He was 74 years old.

Tomlinson invented direct email messages between users on different machines on the ARPANET — the internet’s predecessor — in 1971. Before that, users could only share notes and messages with others on the same computer. He also used the now ubiquitous "@" symbol to indicate networked email.

“A true technology pioneer, Ray was the man who brought us email in the early days of networked computers,” a spokesman for his employer Raytheon Company reportedly confirmed in a statement Sunday. “His work changed the way the world communicates and yet, for all his accomplishments, he remained humble, kind and generous with his time and talents. He will be missed by one and all.”

The cause of his death has not yet been confirmed.

Born in Amsterdam, New York, in 1941, Tomlinson attended college at the Rensselaer Polytechnic Institute and the Massachusetts Institute of Technology in the 1960s, before joining the research and development company Bolt, Beranek and Newman. Tomlinson was working at the company when he made his email breakthrough.

“Tomlinson's email program brought about a complete revolution, fundamentally changing the way people communicate, including the way businesses, from huge corporations to tiny mom-and-pop shops, operate and the way millions of people shop, bank, and keep in touch with friends and family, whether they are across town or across oceans,” Tomlinson’s official biography on the Internet Hall of Fame says.

At the time, computers were very expensive and few people had access to them. In an interview with the Verge in 2012, Tomlinson said he didn’t realize email was a “big deal” until the early 1990s.

“It was a novelty at the time, and there’s a fairly direct path from that early program, including the @-sign and the naming of the fields with in the headers,” Tomlinson said.

In an interview with NPR in 2009, Tomlinson explained his reasoning behind using the @ symbol. One of the key reasons, he said, was that the symbol — now used to designate a user from its host — wasn’t commonly used in computing back then, so there wouldn't be too much confusion. 

“It means "user 'at' host,” Tomlinson said. “It's the only preposition on the keyboard.”

“I see email being used, by and large, exactly the way I envisioned. In particular, it’s not strictly a work tool or strictly a personal thing,” he told the Verge. “Everybody uses it in different ways, but they use it in a way they find works for them.”