How to Unsend an Email in Gmail
Maybe it was just a spelling error. Maybe you hit Reply all by accident. Or maybe you sent the email to the wrong person, and you definitely, definitely don't want that person reading it, because it kinda sorta might contain something super embarrassing.
If you use Gmail, you're in luck. Gmail has recently introduced a feature that lets you unsend any email up to 30 seconds after you've sent it.
This feature—called Undo Send—must be turned on before you can use it. Afterward, you'll be able to take back your most recent email in a single click.