1. Anatomy of Colors

Colors can be explained scientifically, mathematically, and perceptually. Here are the main aspects:

A. Basic Color Theory

• Primary Colors: Red, Green, Blue (in light → additive model) / Red, Yellow, Blue (in pigments → subtractive model).
• Secondary Colors: Colors formed by mixing two primaries (e.g., cyan, magenta, yellow in light).
• Tertiary Colors: Mixing a primary with a secondary (e.g., red-orange, blue-green).

B. Color Models

1. RGB (Additive)
   • Used in screens and digital devices.
   • Range: 0–255 per channel → 16,777,216 possible colors.
   • Example: (255, 0, 0) = pure red.
2. CMYK (Subtractive)
   • Used in printing.
   • Cyan, Magenta, Yellow, Black.
   • Works by subtracting light.
3. HSB/HSV (Perception Model)
   • Hue: The “type” of color (0–360°, e.g., red = 0°, green = 120°, blue = 240°).
   • Saturation: Intensity (0% = gray, 100% = pure color).
   • Brightness/Value: Lightness (0% = black, 100% = full brightness).
4. HSL (Hue, Saturation, Lightness) – similar to HSV but lightness balances between black and white.

C. Dimensions of Color

• Hue → what color it is.
• Saturation → how vivid or dull it is.
• Value/Brightness/Lightness → how light or dark it is.
• Together, these form a 3D color space (like a cylinder or sphere).

2. Total Number of Color Combinations

This depends on the system we are talking about:

• Human Eye: Can perceive about 10 million colors.
• Standard RGB (8-bit per channel):
  • Red = 256 shades
  • Green = 256 shades
  • Blue = 256 shades
  • Total = 256 × 256 × 256 = 16,777,216 possible colors.
• CMYK (8-bit per channel):
  • 256 shades for C, M, Y, K.
  • Total = 256⁴ = 4,294,967,296 possible colors.
• Advanced HDR / 10-bit color (used in high-end displays):
  • 1024 shades per channel.
  • Total = 1024³ = 1,073,741,824 colors.

3. Color Combinations in Design

If you mean pairing or mixing colors (not digital encoding):

• With 16.7 million colors, the number of possible two-color combinations is: (16,777,2162)≈1.4×1014\binom{16,777,216}{2} \approx 1.4 \times 10^{14}(216,777,216​)≈1.4×1014
• For three-color palettes: (16,777,2163)≈7.8×1020\binom{16,777,216}{3} \approx 7.8 \times 10^{20}(316,777,216​)≈7.8×1020

So the possible design combinations are astronomically large.

✅ Summary:

• Colors are defined by hue, saturation, and lightness/brightness.
• In RGB, we get 16.7 million possible shades.
• In CMYK, about 4.29 billion.
• In 10-bit HDR, over 1 billion.
• When combined in pairs or palettes, the combinations explode into trillions or more.