When you click on an email, you likely don't think much about the swift journey it made from the sender's inbox to yours.
But some mail providers still send content over unencrypted connections, so Google plans to notify Gmail users if this is the case.
Google already defaults to HTTPS-the Web prefix indicating an encrypted connection-in Search, Gmail, and Drive, and started encrypting all Gmail messages last year.
And Google said today that encrypted messaging is on the rise: Since 2013, the number of encrypted emails that Gmail received from non-Gmail senders increased from 33 percent to 61 percent.
Because of that final 39 percent, though, Google will serve up warnings.