Two-factor authentication (also called two-step verification) adds an extra layer of security to your personal online accounts that you regularly sign in with using an email address/username and password. By enabling this extra security feature, you can essentially prevent hackers from accessing your accounts if they happen to obtain your sign-in details.

Over the past few years, several popular online platforms have added two-factor authentication to their security features to better protect their users. Enabling it typically involves adding a mobile phone number to your account. When you sign in to your account from a new device, a unique code will be texted or phoned to you, which you'll use to enter into the site or app for verification purposes.

Having a strong password isn't enough to guarantee protection online these days, so enabling two-factor authentication on every online account that allows you to do so is always a good idea. Here are 10 of the most popular online platforms that offer this extra protective security feature plus instructions for how to set them up.