Last week, Google rolled out a disappearing-email option for Gmail called "confidential mode." The feature lets users set an expiration date on emails before sending so that the contents are inaccessible after a certain period.
Confidential mode is available to users with personal accounts who opted into the new version of Gmail last month, when Google announced the latest changes to its email application. Some of the new Gmail features were available right from the start, but others - like confidential mode - are rolling out more slowly.
It won't be available to corporate accounts until a later, unspecified date, but if you have a personal Gmail account, you can turn it on and use it right away.
Here's how to find, turn on, and use Gmail's new confidential mode.