The Changhong UHD55B6000 has a maximum display resolution of 4K Ultra HD. That's over four times the display resolution of the most common HD type of Full HD. 4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.
A 4K Ultra HD HD type is in fact the best display resolution across all similar spec televisions that have been around for a comparable time to the UHD55B6000.
Across comparable types of television the worst display resolution is Full HD.
4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.