The 49UF6909 has a maximum display resolution of 4K Ultra HD. That's over four times the display resolution of a Full HD television, which is the most frequently found display resolution. 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 amongst all TVs that were released around the same time as the 49UF6909.
An HD Ready HD type is the worst display resolution amongst comparable types of TV.
4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.