There should be a stark contrast. Make sure the same is true for followed and unfollowed link colors. Also, only some colors are displayed without dithering on both Macs and PCs. Your page will look best if you use one of these colors for the background. Lynda Weinman provides a page listing all of these colors.
Some people use text-only browsers.
Even more use a graphical browser with image-downloading turned off by default. Don't require your audience to download a large image just to navigate your site. If your web page contains extensive information or is long and wordy, split it into multiple pages for quicker loading and ease of use. Not everyone wants to have MIDI music automatically played when they visit your page. If you must include music, make the user push a button to have it played.