Blue and green are mixed to create teal. Teal is a color that falls into either the secondary or tertiary color wheel.
There are three primary colors within traditional color media, such as ink, paint, and pastels, as well as within the more modern color spaces used in color printing. In traditional media, the primary colors are red, yellow and blue. RGB is the abbreviation for the color wheel in traditional media. Red, green, and blue are the primary colors in modern media, for which the color wheel abbreviation is RYB. Certain settings utilize a CMYK color wheel abbreviation, which represents cyan, magenta, yellow and key, where the color "key" is black.
Because of the difference in primary colors, the specific set of secondary and tertiary colors differs between the two media but are based on the same principle: two primary colors mixed in equal parts yield a secondary color and a primary color mixed with a secondary color yields a tertiary color. In traditional media, the primary color blue is mixed with an equal part of yellow to create green. Green is then mixed with more primary blue to create a shade of teal, which is a tertiary color. In more modern media such as that used to make inks for color printing, teal is a secondary color since green and blue are both primary colors. The shade of teal may be light or dark depending on the saturation of colors in the mix.