Unmanned aerial vehicle (UAV) is an aircraft designed to fly missions without a pilot on board. UAV’s are sometimes called drones, remotely piloted vehicles(RPV's), or remotely operated aircraft (ROA). UAV's are primarily used by national armed forces. Advanced electronics systems enable UAV’s to collect and transmit large amounts of information.
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From Kinney, Jeremy R. "Unmanned aerial vehicle (UAV)." World Book Student. World Book, 2017. Web. 6 Feb. 2017.
Drones are referred to in many ways. Use some of these terms when searching for information about drones:
"unmanned aerial vehicle"
"remotely piloted aircraft"