Basically what i want is that there is a div that is about 100px from the top , now what i want is as the user scroll down the div remains at top 

i know by using css position:fixed; i can achieve that but the problem is it fixes the div t its position like if the div is 100px down it will fix the div there even if we scroll down the div remaisn 100 px from the top, 

what i want is if we scroll down the div moves up and stays at the top