Pharmacognosy deals with medicinal drugs that are derived from plant or natural sources. It also defined as the study of crude drugs. Although most pharmacognostic studies focus on plants and medicines derived from plants, other types of organisms are also regarded as pharmacognostically interesting, in particular, various types of microbes (bacteria, fungi, etc.), and, recently, various marine organisms. secondary metabolites i.e. study of natural product molecules the term defines as Pharmacognosy as that is useful for their medicinal, ecological, gustatory, or other functional properties.