The highest display resolution of the UN48JS8500 is 4K Ultra HD. That's over four times the display resolution of the most frequently found HD type of Full HD. 4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.
This television's display resolution (4K Ultra HD) is in fact the best display resolution amongst all TVs that have been around for a similar time to the UN48JS8500.
The worst display resolution amongst comparable types of television is HD Ready.
4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.
Other 4K Ultra HD TVs currently available that you might want to look at include the Panasonic TX-48CXW404, the Samsung UE40JU6465, or the LG 49UF7767 (£1,059.77) which is cheaper.