Topics represent the range of information in gerontology, covering biological, medical, psychological, and sociological topics as well as social and public policy issues. Articles range from very specific, for example, Congregate housing or Fluid balance, to more general essays, such as Bereavement or Visual arts and aging. About one-third to one-half of the articles focus on biological, medical, or psychological aspects of aging. There are also good treatments of social policy — a history of Social Security, articles on adult protective services, housing options, etc. Many of the articles are broken into segments. Cellular aging has a general overview article, then four more-specific ones dealing with such issues as cell death or DNA. Long-term care and Retirement are similarly broken into segments. This is a useful approach when the audience may vary in levels of familiarity with the topics.