This Color Display Program is VERY user-friendly and at the same time quite powerful. It can display ALL the 16,777,216 possible colors from "000000" through "FFFFFF".
If this is a bit overwhelming, try this link

1) The left side of the page controls the background color and the right side controls font (or text) color.

2) Each of the 6 rows consists of the characters:

Rolling the mouse over any of these characters will change the colors.
Rows 1 & 2 control the amount of RED, rows 3 & 4 GREEN and rows 5 & 6 BLUE.
Rows 1, 3 and 5 are the "coarse" controls and rows 2, 4 and 6 are for "fine" adjustments. Each change of the "coarse" row equals the entire length of a "fine" adjustment row.

3) With EVERY color change, the 2 output boxes will display the six digit "hex value" of that color.
For example, the value for blue is "00 00 FF".

4) This program is quite handy for experimenting. When you create a color you like, write the numbers down and use it on your webpage(s).

But enough talk - you'll learn quickly just by doing.
Have fun finding new colors and color combinations.