In this article, we highlight the possible benefits, as well potential threats, related to the widespread use of robots. We follow the view that a robot cannot be analyzed on its own without taking into consideration the complex sociotechnical nexus of today's societies and that high-tech devices, such as robots, may influence how societies develop in ways could not be foreseen during the design of the robots. In our survey, we limit ourselves to presenting the ethical issues delineated by other authors and relay their lines of reasoning for raising the public's concerns. We show that disagree ments on what is ethical or not in robotics stem often from different beliefs on human nature and different expectations on what technology may achieve in the future. We do not offer a personal stance to these issues, so as to allow the reader to form his/her opinion.