4K and 1080p refer to the resolution of a display, which is the number of pixels it has horizontally and vertically. A 1080p TV has 1920 horizontal pixels and 1080 vertical pixels, while a 4k TV has 3840 horizontal pixels and 2160 vertical pixels. The name 1080p refers to the number of vertical pixels, while 4k refers to the number of horizontal pixels. This means that a 4k display has more than four times the amount of pixels as a 1080p display, resulting in a sharper picture. It's important to note that not all upscaling is created equal, and certain companies have developed better programs to do it effectively.
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