Every year, people from all over the world get information from the United States National Library of Medicine in Bethesda, Maryland. The library is part of the National Institutes of Health. It is the world's largest center of medical information. Doctors, scientists, teachers and historians use the library. So do people who just want to know more about health and sickness.

Thousands of people visit the Library near Washington, D.C. Others get information by computer. For example, people can get health information from a National Library service called Medline Plus. This service cannot identify or advise about individual cases of disorders. But it provides general knowledge about more than six-hundred-fifty diseases and conditions.

A Medline Plus dictionary includes descriptions of medical words. For example, you might hear that someone has had an appendectomy（阑尾切除术）. In the medical dictionary, you can learn that the person has had an operation to remove a part of the intestine（肠）called the appendix（阑尾）.

Drug information on the site describes medicines. Suppose you want to know the possible effects of taking the pain-killer aspirin. You can check a long list of drug descriptions. You can get Medline Plus services through the National Library of Medicine's Web Site, w-w-w dot n-l-m dot n-i-h dot g-o-v. Information appears in English and Spanish.

The Library also offers a Web site especially for older adults and their families. It is called NIH Senior Health, found at w-w-w dot n-i-h-s-e-n-i-o-r-h-e-a-l-t-h dot g-o-v. The National Library created the site with the National Institute on Aging. The site makes it possible for people to find current information from National Institute of Health centers. For example, older people can learn the latest news about the treatment of heart disease or osteoporosis（骨质疏松症）, a bone disorder.

The site designers developed NIH Senior Health from Institute on Aging studies about changes in the thinking abilities of older people. These include understanding, learning, memory and ability to see. Because of these changes, the site contains print that can be made bigger and sharper. Information has been kept short. And a "talking" operation can speak the words.

This VOA Special English Health Report was written by Jerilyn Watson.