Sign to unlock only works if you haver least one registered user. When you sign to unlock, the user desktop, private data, projects system, apps, media are shown.
The sign is made by drawing a continuous line over a matrix of simple figures Like circles, boxes and triangles. You have to conect at least six symbols in a single finger movement (conecting the dots).
When you unlock by sliding, not by signing, you access to the default public desktop. The default public desktop doesn't contains any personal data, photos, email accounts etc. No recent items are shown in the apps and there is not home location. You can browse the web, access to the public projects system, public downloads and all the media, apps, tapps and control surfaces marked as public (by default) .