Good Gear Guide
In Pictures: A visual history of OS desktop enviro...
April 6, 2011 – The initial release of GNOME Shell, a complete redesign of GNOME that accompanied the 3.0 release, ushered in a new era. GNOME Shell contains many usability features that have been around for a long time now: Docks, Window management options where all windows are visible at once, virtual desktops, and many others. Likewise, GNOME Shell's application launcher has a fair bit in common with Ubuntu's Unity application icon grids with searchability. One interesting new feature is a refinement to the way virtual desktops are handled: there is no longer a set number of them. When you open an application, a new empty desktop is created, essentially insuring that you will always have one empty virtual desktop.
In Pictures: A visual history of OS desktop environments