What is the meaning by saying lowest and highest value of color code?

Question

I don't extremely clear about this define: Zero represents the lowest value, and F represents the highest.
What is the meaning when you say the lowest value or the highest value. It is for the strong, the type or any reason. Can anyone help me to make it clearer?
Exp: #000000 this is black code right? So I must understand that Black is the lowest color? Oh but I don't understand what is the lowest color :( It is so confuse with me.

Answer 1

#000000 black
#FFFFFF white

This is a hexadecimal RGB (red, green, blue). A hexadecimal (16 base) number can contain 16 values per place 0-15. 0 (zero) being the lowest and F being the highest. 0 1 2 3 4 5 6 7 8 9 A B C D E F are the possible values where A is 10 and F is 15.

The first 2 places are for R (red) the second 2 for G (green) and the last 2 for B (blue).
Sometimes you may see an additional 2 places for A (alpha) opacity. Depending on what you're working with this may be ARGB or RGBA.

These numbers also compound as you group 2 together giving you a decimal range with 256 possible values of 0-255.

00 = 0
0F = 15
10 = 16
20 = 32

The hexadecimal number in the first (left) place increments the total value by 16 with each increase. While the second (right) increments normally.

Play around with the rob values here to get an idea of the value changes.
http://www.webpagefx.com/web-design/hex-to-rgb/