Lost in the world of Colours

I just don't get it. I mean yeah, I can easily edit scripts that use R,G,B to determine colours but when it comes to "indexes" and "hues" I'm lost. I know there are colours in the windowskin image like below but what about when a script asks for "hue", a value between 0-360? 

 

e.g. Mog Hunter scroll bar script:

   SCROLL_BAR_COLOR = [72,96]

   SCROLL_BACKGROUND_COLOR = [64,96] 

I'm like :

Had to download the demo and look at the script to check it out.

Those values go here:

Rect.new(x, y, width, height)With SCROLL_BAR_COLOR = [72,96]

it's

sc_rect = Rect.new(SCROLL_BAR_COLOR[0],SCROLL_BAR_COLOR[1],4,8)  =

sc_rect = Rect.new(72, 96,4,8)

Essentially, those aren't colors at all >_>

Therefore, I am also confused. Why would they name it "color" and why be customizable in the first place?

How about scripts where you type value for "HUE"? Like Fog scripts for example?

Hue is just the color. 0 to 360 (359 really) is red to red. Red > Orange > Yellow > Green > Teal > Blue > Purple > Red

Usually this will be accompanied by two more values, Brightness and Saturation. Brightness is the scale of darkness from white to black, and Saturation is the amount of color, to put it in simple terms.

at 100% brightness and Saturation, it'll be at the most vibrant color of the hue. The red will be at it's most reddest red, so to speak.

at 0% brightness and saturation, it'll be black

at 100% brightness and 0% saturation it'll be white

at 0% brightness and 100% saturation, it'll be black