When the first cave dweller discovered that they could make different colored paint pigments by mixing various berries, humans have used color to fully express their thoughts, ideas, and feelings. Colors are strongly tied to memory and emotion. Think of walking into a gray, dim medical waiting room versus one that's colorful, light, and calm. Anytime someone visits a medical waiting room there's bound to be stress and anxiety, but color can be used to help change the feel of a space. That's why interior designers work so hard to carefully choose color schemes that work with the light and space of the area they are decorating. Color also serves to invoke the mood their clients want for the space. People decorating their own spaces can also use color in this way. It just requires a little bit of knowledge about color theory.

Primary Colors

Most young children learn the primary colors very early in life. Primary colors can't be created from other colors. They form the backbone of color theory.

• Color Basics: Red, yellow, and blue are the three primary colors.
• Primary Colours: The three primary colors are the basis for almost all other colors.
• What Are the Primary Colors?: Primary colors can't be created from other colors, but can be mixed together to create an almost endless array of other colors.

Secondary Colors

Green isn't a primary color. Instead, green is created by mixing two primary colors. In this case, blue and yellow are mixed to achieve the secondary color of green.

• What Are the Secondary Colors & How Are They Made: It's important to understand the difference between primary and secondary colors.
• Secondary Colors - A Guide to This Group of Colors: Secondary colors are made by mixing together primary colors.
• Secondary Colors: Green, orange, and violet are the secondary colors.

Tertiary Colors

Tertiary colors are made by mixing a secondary color with a primary color. Their purpose in color theory is to act as a bridge on the color wheel between primary and secondary colors.

• Tertiary Colors: There are six tertiary colors.
• Tertiary Colors - Discovering the Possibilities of Intermediate Colors: Tertiary and intermediate colors are not the same thing.
• What is the Correct Definition of Tertiary Colors?: Conventional wisdom states tertiary colors are the colors between primary and secondary colors on the color wheel, but this is incorrect.

Complementary Colors

Complementary colors are colors that lie opposite of each other on the color wheel. Because of this, they provide excellent contrast with each other. Blue and orange is an example of a set of complementary colors.

• Color Theory 101: Making Complementary Colors Work for You: The three sets of complementary colors are red and green, orange and blue, and yellow and purple.
• The Secret to Using Complementary Colors Effectively: One reason why complementary colors work together is that each pairing contains a primary color.
• The Scientific Reason Complementary Colors Look Good Together: One reason complementary colors work so well in interior design is the way the pairings play off of each other's intensity.

Analogous Colors

Analogous colors are those that lie next to each other on the color wheel. Designers like to use analogous color schemes in interior design.

• What Is an Analogous Color Scheme, and Why Are Designers So Obsessed?: Elle Decor defines an analogous color scheme as one where three colors next to each other on the color wheel are used. One is a dominant color (this is usually a primary or secondary color), a supporting color that's either a tertiary or supporting color, and the t third color is either a mix of the first two or an accent color to provide pops of contrast.
• What Are Analogous Colors And How Are They Used?: Pictures of various interior analogous color schemes are used in this article.
• How to Use Analogous Colors to Craft a Statement-Making Space: The secret to making an analogous color scheme? Balance.

The Color Wheel

Designers and artists use the color wheel as a way to understand and display the relationship between various colors. The wheel is arranged around the primary colors.

• The Color Wheel: Johannes Itten developed the 12-color wheel.
• The Interactive Color Wheel: The interactive color wheel makes it easier for some people to understand how it works.
• The Color Wheel (PDF): Here is a thorough explanation of the theory behind the color wheel.

Color Relationships

There are a few different ways to express the relationships between various colors, hues, and shades. The color wheel is the best-known tool for this, but there are other options as well.

• The Art of Color: Color Wheel & Color Relationships: The color wheel is the most commonly used way to express color relationships, but it is not the only way.
• Color Relationships: Monochrome is one way to describe color relationships.
• Color Scripts: Color Relationships in Support of the Story: Using color in film setups is very similar to using color in interior design.

The Painter's Color Triangle

Painters mix the three primary colors (blue, red, and yellow) to create the other colors they use in their words. The painter's triangle expresses this method of color-making.

• Color Triangle - Basic Color Theory for Artists: The color triangle is another way of expressing the relationship between colors.
• The Colour Theory Triangle: The triangle makes it easier to see complementary colors.
• Triangle vs. Circle: There are reasons to understand and use both the triangle and the circle.

The Printer's Color Triangle

Printmaking, either by hand or using a printer, is a different process from painting. It even uses different colors as its primary colors. The printer's triangle is based on yellow, cyan, and magenta.

• Understanding Your Printer's Color Palette: Understanding how color's print is important for designers.
• Importance of CMYK Color Mode: CMYK is another term describing the printer's color triangle.
• What Do the Different Colors on Your Ink Cartridges Mean?: The theory of the printer's triangle turns into reality via printer cartridges.

Nine-Part Harmonic Triangle of Goethe

Goethe organized his triangle by placing the primary colors (blue, red, and yellow) at the three corners of the triangle. Secondary and tertiary colors are organized within the body of the triangle. This is yet another way to express the relationship between colors in visual form.

• Color Mixing and Goethe's Triangle: When Goethe created his triangle he stated that its purpose was to allow people to "marvel at color's occurrences and meanings, to admire and, if possible, to uncover color's secrets."
• Goethe's Theory of Colors
  (Video): Studying color is a powerful tool in understanding life.
• Johann Wolfgang von Goethe and his Theory of Colours: Goethe developed his triangle in 1749.

More Information on Color and Design

• What is Color Theory?: Color theory dates back to 1666 when Sir Isaac Newton invented the color wheel.
• Color Theory for Designers, Part 1: The Meaning of Color: Color theory is both a science and an art, and understanding color theory is necessary for professional and amateur interior designers.
• What Is Color Theory? Meaning & Fundamentals: Color has the power to influence people's feelings and behaviors.
• A Color Skeptic's Guide to Color Theory in Design: Applying color theory to interior design allows people to move away from all-white interiors but still achieve a cohesive, sophisticated look for their home.
• Introduction to the Psychology of Color: For Interior Designers: Ancient Egyptians realized the power color has over human emotions, and it remains important for that power to be recognized when designing interiors.
• How & Where to Use Color in Your Home: Home Color Palette + Easy Color Hacks: Color theory helps designers build color palettes that work.
• Color Theory 101: Analogous, Complementary and the 60-30-10 Rule: Understanding the science of color theory makes for lovelier interior spaces.
• Color Theory for Decorating: Tint, shade, and tone all play a part when planning to decorate color palettes.
• How to Use Color Theory in Interior Decor: Dark colors can be intimidating but can result in sophisticated, beautiful rooms.
• Color Theory: Knowing how to read the color wheel helps people make better interior design decisions regarding color choice.