When it comes to online security nothing is foolproof, but of all the safety measures available, two-factor authentication is one of the most straightforward and secure. Most of the tech world's biggest players offer two-factor logins, and it seems that Amazon's shopping service — a long-standing holdout — has finally joined in. Although there doesn't seem to have been an official announcement, users with Amazon.com accounts can now turn on two-factor authentication in their account settings.

To do so, simply click "Your Account" from the drop-down menu under your name on Amazon.com, then select "Change Account Settings" and "Advanced Account Settings." Then click "Get Started." You'll be asked to login again, and you can then add Amazon.com to any two-factor apps on your mobile using a QR code (e.g. via Authy or Google's Authenticator app), or get authentication codes delivered to your mobile via text. You can also set up a backup method if your primary authentication device fails and enable a trusted device that doesn't require two-factor authentication every time you log in. It's well worth doing, and while you're at it, why not see if you have two-factor turned on for your other accounts?