When you move the mouse over a link, two things will normally happen:
By default, a link will appear like this (in all browsers):
You can change the default colors, by using styles:
<style>
a:link {color:green; background-color:transparent;
text-decoration:none}
a:visited {color:pink; background-color:transparent; text-decoration:none}
a:hover {color:red; background-color:transparent; text-decoration:underline}
a:active {color:yellow; background-color:transparent; text-decoration:underline}
</style>
If you color the background of your webpages, this could become a necessity!