The ability to print what is seen on a computer screen so that it matches a printer (color matching) confounds even the most experienced. That's because computer monitors, even from the same manufacturer, cannot be made to display colors identically. Also, printers from different manufacturers contain several “libraries” of replacement colors in order to replace pixel values in an image from light (red, green and blue: RGB) to the primary colors for pigments (cyan, magenta, yellow and black: CMYK). Cameras use the primary colors for light and that is the way the digital image is stored and displayed; printers use the primary colors for pigments in ink. Thus, a printer must have a pixel by pixel list of replacement CMYK values for every RGB value in any image for that manufacturer's idea of faithful color matching.