Primary colors are a group of colors that act as a reference for all the other colors. These are the colors from which all other colors can be produced. The primary colors include red, blue, and yellow. Surprisingly enough, all other colors such as green, orange, and black can be obtained by the mixture of these colors in varying quantities.
For instance, when you mix green and red, you get yellow. When you mix green, red, and blue, you get white. On mixing red and blue, you get pink. Similarly, on mixing green and blue you get cyan color. On mixing yellow, red, and blue, you obtain the black color.