Abstract: The contradiction between quality improvement of service (QoS) of Internet application systems and users information privacy is one of the hottest topics in the information system research. It summarizes the research on information privacy psychological boundaries and sensitivity in this field, and includes three main aspects as follows. Firstly, it presents a summary of the definition of privacy in different fields; Secondly, it analyzes the difference between information privacy and similar concepts; Thirdly, it classifies the level of user information privacy from the perspective of information sensitivity.

Key words: privacy; information privacy; privacy attitudes; information sensitivity; privacy level