"Pharmacognosy" derives from two Greek words, "pharmakon"or drug, and "gnosis" or knowledge. Thus, Pharmacognosy (chemistry and biology of natural products) is the study of bioactive natural substances found in terrestrial and marine organisms (plants, animals, or microbes).

Research in pharmacognosy is important because it leads to new forms of biotechnology; new types of therapeutic agents; new molecular probes that can be used to study molecular/cell biology; new pest controls to help protect crops; increased understanding of the pharmacological, ecological and biochemical roles of molecules produced by nature; information on herbal medicines; and new methods for the analysis of drugs, toxins and herbal preparations. Pharmacognosy has undergone significant change in recent years and today represents a highly interdisciplinary science which is one of five major areas of pharmaceutical education.