4k and true 4k is just display resolution talk. If 3840 x 2160 counts as 4k (which TVs have been advertising), 1080p counts as 2k. True 4k would be 4096 x 2160 pixels, but the reason 3840 x 2160 is used more often is because it's 1080p x2, and makes scaling up content cleaner and easier. 1k, 2k, 4k, and even 8k textures…