640x480 (VGA), 800x600 (SVGA), etc came from the computer industry since they had 4:3 CRTs 720p, 1080p came from the TV industry since they always counted vide

640x480 (VGA), 800x600 (SVGA), etc came from the computer industry since they had 4:3 CRTs 720p, 1080p came from the TV industry since they always counted video in "lines" (NTSC is 525 lines) 4K came from the movie industry (the 2005 Digital Cinema specification), since movies have wildly different aspect ratios so counting the vertical doesn't make sense (specifically, it's very rare for movies to be 16:9!)