[thelist] Understanding CSS with 3 digit colors ?

[Rob Smith]

Hi list,

I've been trying to beef up my CSS skills and I've noticed something that
I'm not real familiar with. Would someone please explain to me why people
are defining colors with only 3 hex numbers? For example:

A:hover {
	FONT-WEIGHT: 900; COLOR: #555; Font-Size: 10px;
}

Thanks

Rob.Smith