4K resolution, also called 4K, refers to a display device or content having horizontal resolution on the order of 4,000 pixels. Several 4K resolutions exist in the fields of digital television and digital cinematography. In the movie projection industry, Digital Cinema Initiatives (DCI) is the dominant 4K standard.
4K is defined by the movie projection industry as 4096 x 2160 (at a 19:10 or 1.9:1 aspect ratio) and should not be confused with ultra-high-definition television (UHDTV), which only has a resolution of 3840 x 2160 (at a 16:9, or 1.78:1 aspect ratio).
The use of width to characterize...