Microsoft's new Surface Book hybrid laptop and Surface Pro 4 productivity-oriented tablet both include hardware for biometric authentication using facial recognition. Yet when I reviewed them, I couldn't test out the feature because we didn't have a complete final driver stack.

Since then, we've been given final software loadouts and Windows Hello has sprung into life. Whether using facial, fingerprint, or iris recognition, the Hello process is broadly the same: first PIN login must be enabled and then you register your biometric data. In common with other biometric systems such as Apple's TouchID, the biometrics data never leaves the machine and is securely stored in such a way that it shouldn't be possible for malicious applications to capture or exfiltrate the data. Registration for the facial recognition is easy peasy: the camera looks at you for a few seconds, and you're done.

With Hello enabled, logging in to the machine is as simple as sitting down in front of it. The lock screen shows the Windows Hello "eye" looking around, and the detection is near-instantaneous. It takes longer for Windows to dismiss the lock screen and show the desktop than it does for it to recognize you in the first place. In fact, it's so quick that a kind of delay had to be built in. If there were no delay, locking your PC with Windows+L (or the Start menu option) would be nigh impossible. As soon as you locked the PC, it'd recognize your face and unlock. If Hello recognizes your face immediately it asks you to swipe the lock screen out of the way to complete the sign in, but this only happens when it sees you as soon as you've unlocked the PC. If a few seconds have passed, no additional step is required.

The sensor unit in the Surface Book and Surface Pro 4 includes an infrared camera and light that's used by Hello. This means that it works well even in the dark.

One concern with all these biometric systems is their security; can they be tricked with, say, a photograph or an identical twin? Unfortunately I don't have any identical twins to test with, so I'm not sure just how precise it is. There is, however, an optional feature that is described as offering additional security. Instead of just looking at your face, you can make the system require you to turn your head to the left and right before it unlocks. If nothing else, this should preclude the use of flat photographs to trick the system.

In many respects, these concerns probably don't matter too much. The question is not whether the biometrics are better than a long, strong, secure password, but rather whether they're better than a weak, short, repeated, or perhaps even non-existent password. This isn't about setting a new ceiling on system authentication security; it's about raising the floor. Windows Hello makes it very easy to use something that's better than a bad password.

While we've seen a few systems with fingerprint readers or facial recognition (generally using Intel's RealSense 3D camera), I hope that the Surface Book and Surface Pro 4 push the Windows OEMs to do more in this regard. Perhaps these devices will help make some kind of biometric authentication a standard feature.