Web Design in a Nutshell, 3rd Edition

The href attribute provides the pathname (URL) of the document to which you want to link. URLs can be absolute or relative, as discussed in the next sections.

A text link is marked up like this:

I am<a href="link.html">linking</a> to you!

To make an image a link, enclose the image element in an anchor as follows:

<a href="link.html"><img src="pixies.gif"></a>

By default, most graphical browsers display linked text underlined and in blue, but this presentation can be altered with style sheets. Linked images appear with a blue border by default unless you change this setting with the border style property or the deprecated border attribute in the img element.