What is the origin of the common aspirin?

Aspirin is derived from acetylsalicylic acid, which is a derivative of salicylic acid. Salicylic acid is a mild, nonnarcotic pain reliever used to relieve headaches and muscle and joint aches. Salicylic acid is also called orthohydroxybenzoic acid. It is a white crystalline solid, and it occurs naturally in small amounts in many plants, particularly the various species of spirea. An Italian chemist, R. Piria, first prepared the acid in 1838. Today the compound is made from dry sodium phenolate and carbon dioxide. Most salicylic acid produced commercially is treated with acetic anhydride for the preparation of aspirin.