And of <BR>,
And of what happens when you don't use them. (View the source (below) to see what I mean.)
Here's an image of the Nashville.Net logo.
Here's the same image middle aligned and made into a link .
Here's the same image centered and made into a link with no border:
You can even include text in the link with an image.
All of these images are linked relatively because it's easier to type. They could be linked absolutely, but there usually isn't any need, since you shouldn't link to an image that's not on your server.
To view the source code for this page, (if you're using Netscape) go to the View menu and choose Source....