??? ????? ?? ??? ? ?? ???? ?? ????? ???? ???? ?????? ??? ????? ??? ??? ?????The dirty little bit is actually a time period in the field of Pc. It is also called modified bit. It refers to a tiny bit in memory, which switches on when an update is created to the page by Pc components.??????? ??? ????? ??? ?? ???????? ??? ???? ?? ????. ?????? ??? ????