HSB
(Hue Saturation Brightness)

To explore this,

in the Tool palette,

click the foreground color in Photoshop and

click (approximately in the middle) in the large color picker on the left.

Make Hue = your choice

Make Saturation = 50%

Make Brightness = 50%

Hue

Hue is also what is generically referred to as the color.

Shift the hue slider up and down to change Hue.

Saturation and Brightness will be unchanged.

Saturation

Saturation is basically adding or subtracting the gray value of the hue.

100% saturation has no gray added;

0% saturation is gray.

A desaturated color is gray (possibly a very light or dark gray)

Shift the slider up and down to increase or decrease saturation.

The top is 100% saturated.

The bottom is gray with no hue.

Hue and Brightness are unchanged.

Brightness

0% brightness is black.

100% brightness of the color removes all black from the color.

Shift the slider up and down to increase or decrease brightness.

The top is 100% bright.

The bottom is 100% dark = black

Saturation and Hue are unchanged.