Herbal medicine refers to the study of medicinal plants and other natural resources, which are the foundation of traditional medicine. It also involves the use of minerals, fungal and bee products, some animal parts, and shells. Plants synthesize various chemical compounds, which serve a variety of functions such as defense against diseases, insects, fungi, and herbivorous mammals. Many phytochemicals have been found in plants with established or potential biological activity. A single plant may synthesize a vast range of phytochemicals. There are four main biochemical classes of compounds found in plants, which include polyphenols, alkaloids, terpenes and glycosides. This book provides significant information to help develop a good understanding of herbal medicine. It presents researches and studies performed by experts across the globe. This book will prove to be immensely beneficial to students and researchers in this field.