Backgrounds are silly things. You can do almost anything with them.... So lets get started!
Have you ever wondered how some folks get those "really cool" backgrounds? Well, most are background images. You can use a .GIF or .JPG as a background just as you can in the foreground. In fact, this "sidebar" background you are looking at now is a background image. The Background image goes into the BODY statement at the top of the page. <body background="my_gif.gif" Text="#000000" > Most background images are very small. The HAVE to be. If you use a large background image, it will take forever to download, and the slower your page is to load, the more likely someone will say "screw this" and head for parts unknown. Since your browser will "Tile" your background images, they only need be a few lines high. For example, the background image you are looking at now, is only 5 lines high. If you want a "nifty" looking border on the side without using "frames", you can just put it in a background image. This background image is just one example of what you can do. Use your imagination, but rememeber KEEP IT SMALL!!
Background COLORS are handled a bit differently than background IMAGES. With an image, you would use the statement <body background="my_gif.gif">, but with background COLORS, you would use the statement <Body BGCOLOR="#000000"> (or BGCOLOR="BLACK" either one will work).