Merck & Co (also known as Merck Sharp & Dohme) is a healthcare manufacturer and distributor of pharmaceuticals. The company operates through two segments: Pharmaceutical and Animal Health. The Pharmaceutical segment includes human health pharmaceutical and vaccine products that consist of therapeutic and preventive agents, generally sold by prescription, for the treatment of human disorders. It sells these human health pharmaceutical products primarily to drug wholesalers and retailers, hospitals, government agencies, and managed health care providers. The Animal Health segment discovers, develops, manufactures, and markets a range of veterinary pharmaceutical and vaccine products, as well as health management solutions and services, for the prevention, treatment, and control of disease in major livestock and companion animal species.