According to the Additive Color Theory, white is a color and black is the absence of color. The theory states that white is a combination of many colors, and is produced by combining primary colors red, green and blue light. Black is the absence of these colors.
James Clark Maxwell first described the Additive Color Theory in the mid 1800s. He described different colors as wavelengths organized into bands that allow the human eye to perceive color. He also observed that two of the primary bands of color, red, green and blue, added together produces a brighter color than either component. For example, green plus red light produces yellow light, red plus blue light produces magenta light and blue plus green light produces cyan light. Using unequal amounts of the primary bands creates new colors. This principle is present in television monitors.
The Subtractive Color Theory states that black is a color, and white is the absence of color. This is based on the principle that pigments may be added to one another to produce black, but white is the absence of any pigment. According to Color Matters, white is produced using ground bone, chalk or chemicals such as titanium or zinc, and is a color in the context of pigment chemistry. By the same token, pure black paint is produced with charcoal, iron metals and other chemicals.