A monitor blends varying intensities of red, green, and blue light at each of its pixels. These pixels are so small and close together that the eye is fooled into the perception of many different colors when there are really only three. Choose the Appearance Control Panel and select the Color icon to display the Accent Color menu. Click on the Highlight Color pop-down menu and choose Other. Combining the ideal subtractive primaries in equal amounts produces black.
Printing is based on the subtractive color process.
A printer renders color on paper or other substrates, so it must work with reflected light. To do this, printers use the opposing subtractive primaries of cyan, magenta, and yellow. The printing process uses cyan, magenta and yellow inks to control the amount of red, green, and blue light that is reflected from white paper. These colors are printed on paper as layers of halftone dots in varying sizes and angles to create the illusion of different colors. The effect of varying dot sizes is similar to varying intensities of a monitor's red, green and blue phosphors.