Butter that has been slowly melted, so that the milk solids separate from the fat is called "clarified butter." Ghee is clarified butter that has been simmered until all of the moisture has been removed and the butter takes on a browned, nutty flavor. Ghee has a much higher smoke point and longer life than clarified butter.
Often made at home, but commercially produced in Holland, Scandinavia, Australia and India, available in Indian and Middle Eastern markets.
Tightly wrapped, ghee can be refrigerated up to 6 months and frozen up to a year.