You surf adult related sites...
Many files are stored on your hard drive...
These files show what sites you have visited...
Beware when you download porn!
do a search for ccleaner (formally crap cleaner) which really cleans out your cookies and your history among other things. I've used it a lot mostly to keep crap from being on the comptuer and filling up the harddrive.
i just got a new laptop (because the last one died under warrenty) and it does work with both XP (old laptop) and Vista (new laptop).