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Basic Color Wheel: (clockwise from the top) Red, Red-Orange, Orange, Yellow-Orange, Yellow, Yellow-Green, Green, Blue-Green, Blue, Blue-Violet, Violet, Red-Violet.
Primary Colors: Red, Yellow and Blue are equally spaced on the color wheel and can combine to make any color.
Secondary Colors: Green, Orange and Purple. Combining two primary color creates one of three secondary colors.
Tertiary Colors: When you combine one primary color and one secondary color, you create a tertiary color. For example, Blue and Green creates Blue-Green.
Analogous Colors: Grouping three or four colors that fall in a row on the color wheel.
Complementary Colors: These two colors are directly opposite on the color wheel and when combined as a color scheme in a room, it works. For example, Red and Green. [Color wheel images via hue consulting] For more color ideas: