CMYK color model of the primaries: cyan and yellow produce green, cyan and magenta produce blue, yellow and magenta produce red (these subtractive secondary colors correspond roughly to the additive primary colors), plus layering all three of them resulting in black. With halftoning, a full continuous range of colors can be produced. To improve print quality and reduce moiré patterns, the screen for each color is set at a different angle. While the angles depend on how many colors are used and the preference of the press operator, typical CMYK process printing uses any of the following screen angles: The "black" generated by
Blue–green distinction in language for each of blue (""), green ("") and grey (""). For all three, different shades can be indicated with different (compound) terms, none of them being considered as basic color terms: "bleu " (light blue), "bleu " (sky blue), "bleu " (Navy blue), "bleu " (royal blue); "vert clair" (light green), "vert " (literally: apple green); "gris " (very dark grey), "gris " (literally: mouse grey). French also uses "" for the lighter shade of blue of the sunny sky, that was in turn loaned to English as "azure". Catalan distinguishes blue (') from green (') and grey ('). Other