A hospital ship is a ship designated for primary function as a floating medical treatment facility or hospital. Most are operated by the military forces (mostly navies) of various countries, as they are intended to be used in or near war zones. In the 19th century, redundant warships were used as moored hospitals for seamen. The Second Geneva Convention prohibits military attacks on hospital ships, though belligerent forces do have rights of inspection and may take injured enemy patients as prisoners of war.