If you dig a little deeper, what you'll find is that all 'resolutions' using this type of designation are what is known as "contone" settings.
And what that means is that basically all the information about how and what the printer is doing as it's creating dots is not available to the RIP; it's all handled internally in the printer.
In fact, the setting you use as an example looks like it's from some sort of Epson printer, but typically they display with a -CT at the end, such as 720@720x1440-CT; the CT denotes contone.
The way all printer drivers and printer driver quality settings work with RIP's is that all the settings such as this are supplied to the RIP companies by the printer manufacturers. So these same quality settings for whatever printer you have will also exist in Caldera, or Fiery, or whatever; and I'll note that I don't know of any RIP manufacturer that explains them. They're provided by the printer manufacturer, and there they are.
But how that number breaks down is that the first number indicates the "process resolution", the second one indicates that horizontal print resolution, and the third one indicates the vertical print resolution. And what that means is that the "process resolution" is how the image is RIPped, and the print resolutions are how it is printed.
So it works out that the higher the process resolution, the more data in the actual printing image and conceivably the better quality of the print, but the longer it will take to RIP.
Mike Adams
Correct Color