The first built-in method is Mission Control. If you want to hide one application while working in another, invoke Mission Control. Move your cursor to the top right of the screen, click on the plus-sign (+) button to create a new desktop environment, switch to that environment, and open the application you want to work with.
Repeat for other environments and applications. When you’re ready to move to another application, just switch environments.
One way to switch is to hold down the c and Option keys while clicking in the Dock on the application you want to launch or switch to. When
you do this, the other applications are hidden. Another way is to switch to the application you want to use and then press c-Option-H to hide other open applications.
When you make an application run in full screen, the Hide commands
no longer work. If you want to switch applications, you must use the c-Tab shortcut to bring up the application switcher, use Mission Control, use the Dock, or pull the application out of full-screen mode and switch as you normally would.
Of course, you could simply avoid throwing applications into full-screen mode. Photo Booth launches in full screen by default, but other applications launch in the normal view.
I’m keen on auto-hiding applications I’m not actively working with, but I find Mission Control cumbersome. You have a few options here, including Ben Willmore’s Isolator, a very slick utility. With it you can automatically hide inactive applications, as well as completely hide the desktop. Ben requests payment for his work.
We’re also fans of James Thomson’s US$29 DragThing – a palette-based application launcher. Among its many features is the ability to auto-hide all but the active application