Standard or High Definition: It's All in the Pixel Count
 

Most of us don't think much about the images we look at on a TV, flat-panel display, or on a laptop or desktop computer screen; that is, we don't think about what comprises the image—because our eyes and brain merge all the elements of color, brightness and contrast into a "picture" we immediately see. The process is similar, but not exactly analogous, to what happens when we watch a movie. We don't sit there and dissect the 24 still pictures presented sequentially every second (in the case of a TV program, 30 frames per second).

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