We last left hypertext linking with an HTML document that looked something like this:
<a href="http://www.jpl.nasa.gov/spaceimages/">Another Part of the Universe</a>
and looked like this onscreen:
Though text is probably the most frequently used form of hypertext link object, images can also be used as links.
To use an image as the anchor in the above example, you would replace the text "Another Part of the Universe" with an image tag:
Source:
<a href="http://www.jpl.nasa.gov/spaceimages/">
<img src="nasa-thumb.jpg" alt="Two Merged Galaxies" width="175" height="175" ></a>