Catrin. I doubt that you would be using Marquee on your web site but that is an IE spefic tag and it does not scroll on other browsers - I would guess that as it is non-standard, it doesn't even have to display at all.This leads me to another point. When you test your web site, at a minimum, test it on IE and Netscape as the results could be quite different. Compatibility has been mentioned but remember that not everyone uses the "big 2". I for example, have just switched from using IE as my main browser to using Opera which, incidentally, seems to me to be far more efficient than the other browsers I have used.
Jon