Like most Americans, librarians are computer/technology idiots and don't know anything about computers.
Internet web browsers store a history of the sites that have been visited. By default, this history is kept for up to 20 days and you can review it if you like.
I normally kind of like Dr. Laura. But, based on one of her columns quoted on another thread, Dr Laura evidently thinks cunnilingus is a perversion. No wonder she's a little grumpy at times.