The first time drones without pilots have been used in 1973 over the Vietnam War when a plane went down and no-one perished on account of this new technology. Drones are unmanned aircraft remotely controlled using software-controlled flight strategies. Technically, They are really aerial robots flown autonomously using a GPS https://elliottavpgy.blogdigy.com/the-basic-principles-of-advanced-technology-before-the-flood-42096641