Aroma is a term used to describe a distinctive, pervasive, and usually pleasant or savory smell. It is caused by one or more volatilized chemical compounds that are generally found in low concentrations that humans and many animals can perceive via their sense of smell. While "odor" and "smell" can refer to both pleasant and unpleasant odors, the terms "scent", "aroma", and "fragrance" are usually reserved for pleasant-smelling odors and are frequently used in the food and cosmetic industry to describe floral scents or to refer to perfumes. The sense of smell is not overlooked as a way of marketing products, and the deliberate and controlled application of scent is used by designers, scientists, artists, perfumers, architects, and chefs.