This document discusses drones or unmanned aerial vehicles (UAVs). It provides an introduction to UAVs, including a brief history starting from 1916. It describes the key sub-systems of UAVs including the unmanned aircraft, control system, control link and support equipment. The document discusses various design parameters and applications of UAVs, including disaster relief, search and rescue, sports and armed attacks. It also discusses UAV programs in India and compares Indian and U.S. drones. Finally, it outlines some disadvantages of UAVs such as civilian casualties and hacking risks.