Secondary colors are colors that are created by mixing two primary colors in a given color space. The primary colors are red, yellow, and blue, and the secondary colors are located between the primary colors on the color wheel. There are two types of secondary colors: additive and subtractive. Additive secondary colors are produced by combining light and are brighter than subtractive secondary colors, which are produced by mixing pigments and subtract light.

The secondary colors in the RGB color space are cyan, magenta, and yellow. Blue and green produce cyan, blue and red make magenta, and blue and yellow make green. In the RYB color space, the secondary colors are orange, green, and purple. Orange is mixed from red and yellow, green is mixed from yellow and blue, and purple is mixed from red and blue.

In addition to secondary colors, there are also tertiary or intermediate colors, which are created by mixing a primary color with a secondary color. Examples of tertiary colors include blue-green, blue-violet, red-orange, red-violet, yellow-orange, and yellow-green.

Overall, understanding primary, secondary, and tertiary colors is important in color theory and design, as it can help create effective color schemes and evoke certain emotions or moods.