The color glossary

Accent colorDesign & style A bold color used sparingly to draw attention to the most important things. AchromaticTheory & harmony Without hue: black, white and the grays between them. Additive colorTheory & harmony Color made by adding light. Red, green and blue light combine toward white; screens work this way. Analogous colorsTheory & harmony Colors next to each other on the color wheel. They feel calm and natural together.

BandingScreens & photos Visible steps in what should be a smooth gradient. Bit depthColor models & codes How many steps each color channel can have. 8-bit gives 256 per channel, about 16.7 million colors.

ChromaProperties of color How colorful a color is compared with a gray of the same lightness. The "C" in OKLCH and LCh. CIELABColor models & codes A color space built around human vision, with lightness (L*) and two color axes (a* green to red, b* blue to yellow). CMYKColor models & codes The cyan, magenta, yellow and black ink model used in printing, written as percentages of each ink. Color blindnessAccessibility Seeing some colors differently or less distinctly than most people; red-green types are the most common. Color gradingDesign & style Adjusting the colors of a photo or video to set a mood or a consistent look. Color harmonyTheory & harmony Combinations of colors that look good together, often based on their positions on the color wheel. Color paletteDesign & style A small set of colors chosen to be used together in a design. Color profileColor models & codes Data attached to an image or device that says which color space its numbers belong to. Color psychologyDesign & style How colors can affect mood and perception, shaped by culture and context. Color spaceColor models & codes A defined range of colors with a way of numbering them, like sRGB, Display P3 or CIELAB. Color temperatureProperties of color How warm (orange) or cool (blue) a white light looks, measured in kelvin. Color wheelTheory & harmony A circle of hues in order, used to find colors that work together. Complementary colorsTheory & harmony Two colors opposite each other on the color wheel, like blue and orange. They make each other look more vivid. Contrast ratioAccessibility A number from 1:1 to 21:1 that compares the brightness of two colors, used to check text is readable. Cool colorsTheory & harmony Greens, blues and purples: colors associated with calm, water and distance. CSS named colorsColor models & codes The 140-plus color keywords CSS understands, like tomato, rebeccapurple and steelblue.

Delta EAccessibility A number for how different two colors look. Below about 2, most people can't tell them apart. Display P3Color models & codes A wide-gamut color space used by modern phones and laptops, with richer reds and greens than sRGB. DitheringScreens & photos Mixing pixels of available colors in a pattern to fake colors or smooth gradients that can't be shown directly. DuotoneDesign & style An image made from just two colors, usually a dark and a light.

Earth tonesDesign & style Warm, muted colors found in nature: browns, tans, olives, terracotta and ochre. EyedropperScreens & photos A tool that picks up the exact color from any point on screen or in an image.

GammaColor models & codes The curve that maps stored color numbers to actual brightness, so dark tones get more precision. GamutColor models & codes The full range of colors a device, ink or color space can produce. GradientDesign & style A smooth blend from one color to another.

HalftonePrint Printing tones with tiny dots of different sizes, which blend into smooth color from a distance. HEX codeColor models & codes A six-character code for an RGB color, like #2387FF: two characters each for red, green and blue. HSLColor models & codes A way to describe color by hue, saturation and lightness, which is easier to adjust by hand than RGB. HSVColor models & codes Hue, saturation and value (or brightness): the model behind most color pickers. HueProperties of color The basic family of a color (red, orange, yellow, green, blue, purple) as a position on the color wheel.

Jewel tonesDesign & style Deep, rich, saturated colors named after gems: emerald, sapphire, ruby and amethyst.

LightnessProperties of color How light or dark a color is, from black to white. LuminanceProperties of color How much light a color appears to give off, weighted by how sensitive the eye is to each color.

MetamerismPrint When two colors match under one light but not under another. Monochromatic colorsTheory & harmony A palette built from one hue in different tints, shades and tones.

Neutral colorsTheory & harmony Low-saturation colors like white, black, gray, beige and taupe that support other colors.

OKLCHColor models & codes A modern, perceptual way to write color as lightness, chroma and hue. Supported in CSS as oklch(). OpacityProperties of color How see-through a color is, from fully transparent (0) to fully solid (1 or 100%).

PantonePrint A standardized system of numbered ink colors, used so a color prints the same everywhere. Pastel colorsDesign & style Soft, light colors with low to medium saturation, like baby blue, mint and blush. Primary colorsTheory & harmony The colors you mix to make all the others: red, green and blue for light; cyan, magenta and yellow for ink. Process colorPrint Color printed by layering dots of cyan, magenta, yellow and black ink.

RGBColor models & codes The red, green and blue light model that screens use. Each channel runs from 0 to 255. Rich blackPrint A deeper printed black made with black ink plus some cyan, magenta and yellow.

SaturationProperties of color How vivid or intense a color is, from gray (none) to the purest version of the hue. Secondary colorsTheory & harmony Colors made by mixing two primaries, like orange, green and purple on the painter's wheel. ShadeProperties of color A color mixed with black, making it darker and deeper. Simultaneous contrastTheory & harmony How a color looks different depending on the colors around it. Split-complementary colorsTheory & harmony One color plus the two neighbors of its complement. High contrast, but easier to balance than a straight complement. Spot colorPrint A pre-mixed ink printed as its own color, rather than built from CMYK dots. sRGBColor models & codes The standard color space for the web and most screens. Subtractive colorTheory & harmony Color made by inks or paints absorbing light. Cyan, magenta and yellow combine toward black; print works this way.

Tertiary colorsTheory & harmony Colors between a primary and a secondary on the wheel, like red-orange or blue-green. Tetradic colorsTheory & harmony Four colors made of two complementary pairs, spaced in a rectangle or square on the wheel. TintProperties of color A color mixed with white, making it lighter and softer. Tonal valueProperties of color In art and design, how light or dark a color is. Strong value contrast makes an image readable. ToneProperties of color A color mixed with gray, making it more muted. Triadic colorsTheory & harmony Three colors evenly spaced around the color wheel, like red, yellow and blue.

UndertoneProperties of color The subtle hue underneath a color, like the pink in a warm gray or the green in a cool beige.

Warm colorsTheory & harmony Reds, oranges and yellows: colors associated with heat, energy and closeness. WCAGAccessibility The Web Content Accessibility Guidelines, which set minimum color contrast for readable text. Web-safe colorsColor models & codes A set of 216 colors from the early web that displayed reliably on 256-color screens. White balanceScreens & photos Adjusting an image so white objects look white, removing color casts from the light.

60-30-10 ruleDesign & style A balance guide: 60% main color, 30% secondary color, 10% accent.