EMAIL IS BACK! IT NEVER REALLY WENT AWAY.

FIFTY YEARS IN, EMAIL HAS BECOME MORE ESSENTIAL THAN EVER—AND THE KEY TO UNLOCKING PERSONALIZED AI.

- MARK WILSON

THE FOUNDER OF SLACK ONCE DEEMED EMAIL “THE cockroach of the internet.” He wasn’t the first to lament the extreme survivability of our inbox. From text messages to social media to office messaging platforms, all sorts of communication technologies have teased the promise of killing email by connecting us to others in faster, richer ways.

And yet, more than 50 years after its invention, ye olde email is more popular than ever. Some 1 billion people spend three hours a day in email—adding up to more than a trillion hours collectively per year, according to the email app Superhuman. And there’s no sign of this slowing down. “More people use Gmail every single month than ever before,” says Blake Barnes, head of Gmail product, who oversees the experience of more than 2.5 billion users on the world’s most popular email platform.

To some, email is an endless guilt machine: The average person receives dozens of messages each day but takes action on fewer than five, according to Yahoo. And the range of emails we receive is wild to comprehend: personal notes. Newsletters. Amazon package updates. Dinner reservations. Jira tickets. LinkedIn invites. Passwords we’ve sent to ourselves. Strange conspiracy theory chain letters forwarded along by a second cousin once removed.

Email has become the junk drawer for our digital lives. A catchall for intimate and automated messages, our inboxes contain too much information for most people to process. “Your last 100 emails are more unique than your fingerprint,” says Anant Vijay, product lead behind the encrypted-email platform Proton Mail. “Even if you’re using another app to do something, there’s an imprint left in your email.”

And therein lies the opportunity. Not only is email refusing to go away, it’s becoming more important than ever in our new, data-hungry world. And startups and incumbent tech companies alike are vying to control it.