Signing in with a picture password – Building Windows 8 – Site Home – MSDN Blogs

At its core, your picture password is comprised of two complimentary parts. There is a picture from your picture collection and a set of gestures that you draw upon it. Instead of having you pick from a canned set of Microsoft images, you provide the picture, because it increases both the security and the memorability of the password. You get to decide the content of the picture and the portions that are important to you. Plus, you get to see a picture that is important to you just like many people do on their phone lock screen.

via Signing in with a picture password – Building Windows 8 – Site Home – MSDN Blogs.