Changing Screenshot Formats in OS X

Keyboard shortcuts that can be used to capture screenshots in OS X:

Command + Shift + 3 will take a screenshot of the entire screen and its contents.
Command + Shift + 4 will show crosshairs that can be used in conjunction with the mouse to drag a square around the capture area.
Command + Shift + 4, then press spacebar will give you the ability to click on a specific window to capture only its contents.

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