Are you setting background and text color to your Web page? If not, you may not be happy with what your viewer sees. Many designers think that white is the default and that a background color is only necessary if white is not used. Many other designers think that a background color is not necessary if they use a background graphic. Read more on this topic from James Huggins:
I have my default browser, Firefox, set to show a pink color background when no background is specified so when I visit this page on James site, I see
If I visit his site and he has set the background color, then I see it as he wants it seen.
Rule of thumb: Remember to set the background color and color in your body element.