4K content is the next level of HD with about four times the resolution of regular 1080p HD content. This makes 4K (also called Ultra High Definition or UHD) content look crisp and clean on ultra-high-res screens. If you want the most vibrant image possible, 4K is what you should be looking for.
Surprisingly, traditional cable TV providers offer very little 4K live content and only a small selection of on-demand content. This leaves viewers in a quandary as to where they can find 4K content.