Gerontology (from Greek: γερο, gero, "old age"; and λόγος, logos, "speech" lit. "to talk about old age") is the study of the social, psychological and biological aspects of aging. It is distinguished from geriatrics, which is the branch of medicine that studies the disease of the elderly.
Aging is a multidisciplinary field. This means that the study of aging combines or integrates information from several separate areas of study. Biology, sociology, and psychology are the "core" or basic areas, along with content from many other areas of study such as public policy, humanities, and economics.
Gerontology is the study of the aging processes and individuals as they grow from middle age through later life. It includes:
1. the study of physical, mental, and social changes in older people as they age
2. the investigation of the changes in society resulting from our aging population
3. the application of this knowledge to policies and programs. As a result of the multidisciplinary focus of gerontology, professionals from diverse fields call themselves "gerontologists"