ease of use

Use your iPad as an external display.

Use your mac as a keyboard for iOS and android devices.

Use one mouse/keyboard to control several Macs.

Use your Mac's keyboard on all your devices.

Use a Mac computer as a video surveillance camera.

Use a screensaver as your desktop wallpaper.

Use Quartz Compositions, videos, or Web pages as wallpaper.

Use QuickTime movies as screen savers.

Use your digital camcorder to backup data.

Use your volume keys to adjust the volume in iTunes, via AirPlay.