If you’re not using 2-step verification on your Google account by now then you really ought to get on that ASAP. Two-step verification is one of the best ways to keep hackers from getting at your information stored on Google. Now to make 2-step verification even better Google introduces Security Key.
Security Key is a physical USB key that further keeps your information secure from would be hackers. Two-step verification is pretty simple, after you set it up and you try to log into a device, you are asked to provide a code that is sent to your phone via SMS. In this way Google knows you are who you say you are. Security Key works a little differently.
Today we’re adding even stronger protection for particularly security-sensitive individuals. Security Key is a physical USB second factor that only works after verifying the login site is truly a Google website, not a fake site pretending to be Google. Rather than typing a code, just insert Security Key into your computer’s USB port and tap it when prompted in Chrome. When you sign into your Google Account using Chrome and Security Key, you can be sure that the cryptographic signature cannot be phished.
Security key uses the open Universal 2nd Factor (U2F) protocol from the FIDO Alliance. Security key is free but you will have to find a compatible USB stick to be able to run it.Source: Google Security