Description and use of dppx seems inaccurate

[akorman]

In the FAQ it says:

"DPI is often used for the actual device pixels and Dots Per Pixel (dppx) for the amount of device pixels per CSS pixel (e.g. in Retina displays this will be 2)."

Unfortunately, the term "dppx" is misleading because it implies there are 2 dots displayed for every pixel defined in CSS, when what's really happening is there's a device pixel ratio multiplied on both planes, so on a Retina device 1 pixel defined in CSS is displayed as 4 pixels (2px high and 2px across). A 10x10 pixel box (100 pixels) becomes a 20x20 pixel box (400 pixels) on a Retina device.

It seems like in the table of common devices it would make sense to change the heading from dppx to "Pixel Ratio," or something like that but I'm not sure of a clear, pithy way to update the FAQ to clarify that point.