The default color for hyperlinks on the web is blue, but you can change this if you wish. You assign the colors right after the <body> tag near the beginning of your page and you can also control the colors of links that have already been visited and "active" links. (An active link is one that you've just clicked on with your mouse. The default color for active links is red).
So let's say you want your regular links to be green, your visited links to be orange, and your active links to be purple. Right inside the body tag you'd insert:
<body link="green" vlink="orange" alink="purple" >
The order you put the values in does not matter. You could have listed the alink (active link) or the vlink (visited link) value first. Just make sure you don't forget to include the quotes around the color values.
And of course, you can also use hex values to specify colors that are not on the standard color wheel. Just remember to put the # sign before the hex value.
Lesson # 5 : HTML Tutorial - Assigning Background Colors