High Dynamic Range. It is a standardized term to clearly identify panels capable of displaying a wide color range (over a billion colors). In the 2010's when LED was coming to market the different brands touted many different exaggerated "contrast ratios" (i.e. the amount of shades or degrees of difference between the brightest output and the lowest light output the panel was capable of producing), such as 1,000,000:1, as there was no generally accepted standard unit to measure the ratio. While dealing with much more than just light, HDR can be seen as an attempt to correct this. An HDR label panels means it is capable of producing a minimum of 1,024 different shades of each primary color, resulting in roughly a billion different colors. This is in comparison to Standard Dynamic Range (SDR) which at maximum is 256 difference shades of each primary color, resulting in millions of colors.