What's“visa exemption for resident permit holders”?

Foreigners who have entered China with D, J1, Q1, S1, X1, or Z visas and have obtained the residence permit through public security organs could stay in China, and enjoy multiple entries and exits without a separate visa during the valid period of the residence permit.Those who hold a Certificate of Permanent Residence of Aliens may stay in China, and enjoy multiple entries and exits without a separate visa.