Drugs refer to substances used to prevent, treat and diagnose human diseases, purposefully regulate human physiological functions and specify indications or indications, usage and dosage, including Chinese herbal medicines, Chinese herbal pieces, Chinese patent medicines, chemical raw materials and their preparations, antibiotics, biochemical drugs, radioactive drugs, serum, vaccines, blood products and diagnostic drugs. The quality characteristics of drugs (APIs and their preparations) include effectiveness, safety, stability and uniformity. Medicine is a special commodity because it has the following characteristics: 1. Life relevance; Second, high quality (there are only qualified products and unqualified products, but there is no distinction between top grade and inferior product); (3) public welfare (prevention and treatment of diseases and maintenance of people's health); Fourth, a high degree of professionalism (the professionalism of employees). Fifth, there are many varieties and limited output.