Merck & Co., Inc. is a health care company, which engages in the provision of health solutions through its prescription medicines, vaccines, biologic therapies, animal health, and consumer care products. It operates through the following segments: Pharmaceutical, Animal Health, and Other. The Pharmaceutical segment includes human health pharmaceutical and vaccine products. The Animal Health segment discovers, develops, manufactures, and markets animal health products, such as pharmaceutical and vaccine products, for the prevention, treatment and control of disease in livestock, and companion animal species. The Other segment consists of sales for the non-reportable segments of healthcare services. The company was founded in 1891 and is headquartered in Rahway, NJ.