Contrast and analogy are the principles that define color design.
Contrasting colors are different, analogous colors are similar. Contrast draws attention, analogy groups.
the contrasting red squares stand out from the field of analogous blue-green ones, and capture your attention first.
Choosing colors is a challenging problem in many design scenarios.
In color design, color is specified by three dimensions: hue, value, and chroma. Hue is the color’s name, such as red, green or orange. Value is the perceived lightness or darkness of
the color. Chroma describes its colorfulness. High chroma colors are vivid or saturated, low chroma colors are grayish or muted.