color wheels.

"A color wheel is an organization of color hues around a circle." (http://en.wikipedia.org/wiki
/Color_wheel#History) A color wheel has 12 colors that are each in equal steps. The three primary colors ( red, yellow, and blue) are the three main colors, these colors are separated in the color wheel by three equal spaces on either side. The colors that are equally spaced between the primary colors are the secondary colors, these colors are mixed using the primary colors. Blue + yellow = green, yellow + red = orange, red + blue = violet. The colors that take up the space in between the primary colors and the secondary colors are call the tertiary colors. These colors are red-orange, red-violet, yellow-orange, yellow-green, blue-violet, and blue-green. There are also these things called complimentary colors, these colors are opposites on the color wheel or "opposite in 'hue'"(http://en.wikipedia.org/wiki/Complementary_color). A few examples of this are: red and green, blue and orange, violet and yellow.

In 1611 an astronomer, priest, and Neoplatonist Aron Sigfrid Forsius created the first color system. "In his color circle, between the colors Black and White, Red has been placed on the one side since the classical antiquity, and Blue on the other; Yellow then comes between White and Red, pale Yellow between White and Yellow, Orange between Yellow and Red."(http://www.coloryourcarpet.com/History
/ColorHistory.html). Franciscus Aguilonius created his own color diagram in 1613, this had to do with his work that he did with optics. It didn't come until 1672 when Isaac Newton came up with the first color wheel.



http://webexhibits.org/colorart/color.html
http://www.coloryourcarpet.com/History/ColorHistory.html
Image-http://en.wikipedia.org/wiki/Image:Boutet_1708_color_circles.jpg