Background colors and images
There really isn't too much to talk about when it comes to backgrounds. You can either leave the background as the default color, change it to a color of your own choosing, or have the background be an image. For this page, as with all of the rest, I set the background color myself. The way you do this is to put a BGCOLOR=" " option in the BODY tag. For example, the body tag for this page looks like:
<BODY BGCOLOR="#DCDCDC" (plus some other stuff)>
You can just pick any color you like from any of the thousands of colors possible. I would definitely recommend this option if you aren't going to have an image as your background. You never know what a browser's default background is going to be set at, so it's best to predefine it yourself so your page will look the same to everyone.
The other option is to have an image be your background. This is simple as well. To do this, you just add a BACKGROUND="image_name" option in the BODY tag. It could look like this:
One neat trick that I just recently found out about is the effect that the background image remains fixed, while the text just scrolls over the top of it. To get this effect, all you need to do is add BGPROPERTIES="FIXED" in the BODY tag.
That's it for backgrounds!