Occasionally, you need a picture of what you see on your computer screen. Whether you're dealing with a service technician in another city or are illustrating an article for Web publication, the ability to capture what you see can be critically informative. Mac offers several keyboard shortcuts to capture screen images.
Hold down the "Command," "Shift" and "3" keys simultaneously to capture a picture of your entire desktop. If your audio is turned on, you hear a click similar to that of a camera. The picture saves to your desktop and is named "Screen Shot" plus the date.
Hold down the "Command," "Shift" and "4" keys simultaneously and release to capture a certain area of the screen. A cropping tool appears. Click and drag the tool to select the area of the screen you would like to capture with the tool. Release to capture the shot.
To do a screen capture of a specific application window, hold down the "Command," "Shift" and "4" keys simultaneously and release. Click the spacebar and a camera icon appears. Move the camera icon to the application window you want to capture and click in the window.