Let's change the intro === 
 The definition «Overscan is extra image area …» is what's confusing. Overscan is something done by the display! Everyone knows there is no «extra» in an image going into a computer display, and when swapping it with a TV results in chopped edges, that's obviously the TV's fault. Nikevich's explanation «… aims the beams beyond the visible edges» would be a better intro, and even hints at the origin of the word.   

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