Which color model is additive?

• A. CMYK
• B. RYB
• C. CMY
• D. RGB

Answer: (D)

Additive color deals with light: you create colors by adding light together, so brightness increases as more colors are combined. The model that uses red, green, and blue as its primaries is RGB. On screens, each pixel emits red, green, and blue light, and when all three are turned on at full strength you get white. That direct relationship—adding light to produce brighter colors—defines the additive model.

The other common color models are subtractive, designed for pigments and inks. CMY (and CMYK, which adds black) work by absorbing parts of the spectrum, so mixing pigments tends to darken and move toward black rather than toward white. RYB is a traditional painter’s color system, also subtractive. So RGB is the additive model, while CMY/CMYK and RYB are subtractive.