I am starting a series of posts on Color Theory. It has been of interest to me, and I think it will be beneficial to you as you create your cards and scrapbook pages.
Primary Colors are red, blue and yellow. These are the colors from which all other colors are made.
Secondary colors are violet, green and orange. They are made by combining 2 primary colors. For example,
red + blue = violet, blue + yellow = green, red + yellow= orange.
Primary and Secondary Colors combine to make what are called Tertiary Colors. These include yellow-green, yellow-orange, red-orange, red-violet, blue-violet, and blue-green.
Let me show you a few pictures to explain. I cut some paper pieces and placed them around the color wheel so that you can see how the colors interact.