Ray Tomlinson, the computer programmer who transformed direct email messaging back in 1971 died on March 5 from a fatal heart attack. The man credited with saving the ‘@’ symbol and giving it purpose was 74.

Thank you, Ray Tomlinson, for inventing email and putting the @ sign on the map. #RIP

— Gmail (@gmail) March 6, 2016

It was known as the SNDMSG command, which sent mail to other computers at a time when notes could only be sent via the same computer. The networked messaging system was revolutionized when he added the important ‘@’ symbol to be sure of his recipient, which, as we all know, changed the game.

The next time you slide into someone’s DMs remember, Ray Tomlinson.

*Update: An earlier version of this post said he was the inventor email, upon further research it was Shiva Ayyadurai who actually invented email messages. Our bad.

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