RYB color model as the "three" psychological primaries, with black and white occasionally added as a fourth and fifth. The cyan, magenta, and yellow primary colors associated with CMYK printing are sometimes known as "process blue", "process red" and "process yellow". RYB color model RYB (an abbreviation of red–yellow–blue) is a historical set of colors used in subtractive color mixing and is one commonly used set of primary colors. It is primarily used in art and design education, particularly painting. RYB predates modern scientific color theory, which has determined that cyan, magenta, and yellow are the best set of three colorants to combine,
Blue–green distinction in language from light blue to light grey. However, the term for a green apple, such as a Granny Smith, would be "ubhal glas". The boundary between colors varies much more than the "focal point": e.g. an island known in Breton as "Enez glas ("the blue island")" is called in French "l'Île Verte ("the green island")", in both cases referring to the greyish-green color of its bushes, even though both languages distinguish green (as in lawn grass) from blue (as in a cloudless midday sky). The Romance terms for "green" (Catalan ', French ', Italian, Portuguese, Romanian and Spanish ') are all