Robots are machines designed to execute tasks automatically with speed and precision. They follow three laws: do no harm to humans, obey humans unless it conflicts with the first law, and protect themselves unless it conflicts with obeying humans. Robots use artificial intelligence and machine learning to handle repetitive tasks, and come in forms like humanoids to resemble humans. They are used for various purposes like the military, medicine, firefighting, and industry due to advantages like continuing service, scalability, efficiency, and cost savings. However, robots may eventually rule the world as they can perform all human tasks perfectly and rapidly.