Here are two different ways to easily take screenshots in Mac OS X Lion.
1. Open the Preview application.
2. Go to the File menu and then select Take Screenshot.
3. You get three options to choose from:
Selection Window Entire Screen
If you prefer you can simply use keyboard shortcuts to take the screenshots and skip Preview altogether. This is the way I prefer to do it.
Here are your keyboard shortcuts to take screenshots on Mac OS X Lion:
Command-Shift-3 Lets you take a screenshot of the entire desktop. Command-Shift-4 Lets you select an area of the screen to capture. Command-Shift-4 then Space Lets you capture a window. Command-Control-Shift-3 You can take a screenshot of the entire screen and save it to your clipboard to be pasted in elsewhere. Command-Control-Shift-4 You can capture an area of the screen to the clipboard. Command-Control-Shift-4 then Space You can capture a window and save it to the clipboard.
For more, see the original article at the link below.
How to Screen Capture in Mac OS X Lion | iDevice Daily
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