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If it does, you will see a full-screen icon that looks like two diagonal arrows in the top-right of the program window. Use the methods above to switch between your spaces, one of which will now contain only your full screen application. To switch a full screen program back to normal, move your mouse to the top right corner of the screen. Click the blue icon that appears in the top right of the full screen program window. Your program will return to its original space.

Summary:
Check if the application you are running supports full screen mode. Click the icon to switch to full screen mode. Leave full screen mode when finished.