hello
if u have a page which contains lots of information so ur page size get increase....and the user who is visiting the website and goes at the bottom of the page so its very boring for them to get at top by scrolling the scroll bar....so to overcome the problem u can give a link at the bottom and write following javascript code behind the page the code is....
<a href="javascript:scroll(0,0)">Go Top</a>
its simple :)
njoy