That is the viewable screen real estate on that display.


Look down on right...


http://store.apple.com/us/product/MB382LL/A

Technical Specifications

Screen size: 24 inches (diagonal viewable)
Screen type: TFT active-matrix LCD
Resolution: 1920 by 1200 pixels
Colors: 16.7 million
Viewing angle: 178 horizontal; 178 vertical
Brightness: 330 cd/m2
Contrast ratio: 1000:1
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http://davidbearphotography.com/
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It appears that autocorrect has become my worst enema.
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