The term "4K" refers to the horizontal resolution of such screens as they are all about 4, 000 pixels in width.

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The UltraHD format was voted by the Consumer Electronics Association (CEA) last October and refers devices with a horizontal resolution of at least 3, 840 pixels.

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The "1080" part indicates that 1, 080 horizontal lines of resolution are displayed.

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Let's be clear: the 1, 792 x 768 resolution ultimately amounts to your garden-variety 1, 366 x 768 with some extra horizontal pixels.

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