This is about the basic knowledge about color theory which is widely used in design.

1. Color Theory Basics

2. Colors:
Primary
Secondary
Tertiary

3. Complementary
colors:
Any two colors
which are
directly
opposite to
each other.

4. Double
complementary
color scheme
Double
complementary
Color scheme

5. A split
complementary
color scheme is one
where a
primary color is used
with the two
analogous colors to
its complement

7. Analogous colors are groups of three colors that are next to each other on the
color wheel. An analogous color scheme creates a rich, monochromatic look.

8. triadic color scheme uses colors that
are evenly spaced around
the Color wheel. Triadic color
harmonies tend to be quite vibrant,
even if you use pale or unsaturated
versions of your hues.
Tetrad/Tetradic is a special variant of
the dual color scheme, with the equal
distance between all colors. All four
colors are distributed evenly around
the Color wheel causing there is no
clear dominance of one color.

9. Triadic color scheme photo and analysis

11. Tint. Tone & Shade

12. Color value refers to the
lightness or darkness of the
hue. Adding white to a hue
produces a high-value color,
often called a tint. Adding
black to a hue produces a
low-value color,

13. This Photograph has a Triadic
color scheme