The highest display resolution of the UN55HU9000 is 4K Ultra HD. That's over four times the display resolution of a Full HD television, which is the most common display resolution. 4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.
This TV's display resolution (4K Ultra HD) is actually the best display resolution across all large TVs that have been on the market for around the same time as the UN55HU9000.
Across comparable types of TV the worst display resolution is Full HD.
4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.