An aircraft is a medium which is able to fly throughout the Earth's atmosphere or through any other atmosphere. Most rocket vehicle is not aircraft because they are not support by the surrounding air. All the human action which environs aircraft is called aviation.
Manned aircraft are flying by a pilot. Until the 1960s, unmanned aircraft is called drones. During the 1960s, the U.S. military bring the term distantly piloted vehicle (RPV) into use. More lately the term unmanned aerial vehicle (UAV) has turn into common.