Color Names vs. Color Numbers
Although
color names are easy to remember,
fewer than 200 different colors are available and color names aren't
supported by as many browsers.
Color numbers
allow use of 16.7 million colors and are compatible with all browsers
that support color.
Note that most browsers will accept either "#000000" or "000000" as a
color number format, but using "#" is the standard.
Also, in HTML, hexadecimal numbers are not case sensitive, so "#AACCFF" and
"#aaccff" display the same color, whereas all lowercase, "#aaccff", is
required by XHTML. Thus, we will always use lowercase.
