Mac OS X Lion brought us Mission Control, which brings together Exposé, Dashboard, Spaces, and full-screen apps to give you one place to see and navigate everything running on your Mac.I was never a fan of Exposé, Dashboard or Space in previous OS X releases, but when full-screen apps came to Lion, I found it to be a dramatically different experience. If you haven’t tried it, I highly recommend you give it a chance. To make working with Mission Control easier, Apple have included a few keyboard shortcuts.
Invoke Mission Control
Control + Up Arrow or F3
Return to Desktop from within Mission Control
Control + Down Arrow or F3
Switch between Spaces
Control + Right or Left Arrow