The medical effects of many substances have been continuously confirmed over time. They have curative effects and are also toxic. A well-known example is salicylic acid, which has been used to treat rheumatic joint pain as early as ancient times. Salicylic acid can suppress fever and pain, but it is extremely uncomfortable for the gastrointestinal tract. Therefore, at the end of the 19th century, the chemist Hoffmann He tried his best to find drugs more suitable for the human body for his father who was suffering from rheumatism. He mixed salicylic acid with acetic anhydride to obtain acetylsalicylic acid, which was approved for clinical use in 1899 and has since been known to the world as "aspirin".

In the more than 100 years since drug research began, the methods of drug research have changed dramatically. In the past, researchers used a trial-and-error approach, that is, trying various candidate compounds one by one. But now this approach has become impractical because the number of compound types has grown to an astronomical number. Therefore, new methods of developing drugs are constantly emerging, especially computer technology, which plays a very important role in drug design.