Arthritis isn’t a single disease; the term refers to joint pain or joint disease, and there are more than 100 types of arthritis and related conditions. People of all ages, races and sexes live with ...

This iceberg in Scoresby Sound, East Greenland, is one of many frozen sights in the country. Photograph by Frans Lanting, Nat Geo Image Collection Craters at Lake Myvatn in Iceland are among the ...