Introduction to Various Color Systems and Models

RYB (Red, Yellow, Blue) is the traditional color model used in art and design education. It's based on the primary colors from which other colors are derived. Mixing these primaries yields secondary colors—orange, green, and purple. RYB is instrumental in teaching color mixing and understanding color relationships, crucial for painters and traditional artists.

However, it's not a scientific color system, and the colors you can achieve with it are often limited by the pigments available, etc.

These are your bread and butter in digital and print design. RGB and its digital derivates are oriented around lighting up the dark monitor panel, while CMYK was designed for blending inks over a bright piece of paper.

These color models and codes are needed because they provide a language for specifying color. However, these specific ones are designed around technical implementation, and perform quite poorly for color mixing and harmony. Even converting RGB to CMYK can lead to color accuracy problems.

The CIE, or Commission Internationale de l’Éclairage, is the organization that first introduced the CIE XYZ color space. It's based on a mathematical model that represents color as perceived by the human eye. It's all about perceptual uniformity, where equal changes in values should result in equal visual changes. From that, numerous color spaces were developed, and we'll into those in our next section.

Below, you can see how the sRGB and Display P3 color space fits with-in CIE XYZ:

Fun fact: since RGB does not scale well into CMYK, advanced software will often convert the digital color to a CIE format, and then to CMYK. Similarly, many photo editing programs utilize this color space behind the scenes when applying color corrections, converting to grayscale, etc, to ensure optimal uniformity.

Each color system has its use. RYB reigns in art, RGB in digital screens, CMYK in print, and CIE in color standardization. Understanding these systems lets you work with various tools to achieve the best outcome for your task.

There are also many other color systems for video, color matching, and so on. However, when it comes to discovering new color combinations and achieving harmonious graphic design, I believe that the CIE XYZ derivates offer the best solution, and much of “Advanced Color Theory” section is focused on expanding on their use.