What is the main conflict in R.U.R. by Karel Capek?

The play's main conflict in centered around class conflict. With the creation of robots, the earth is divided into two classes: those who have control and those who are controlled. The robots form this latter class, which is designed to be exploited. The robots are little more than slaves who are expected to work until they can work no longer, a period of about twenty years. They are designed and treated as though they have no feelings, no needs, and no expectations. The robots' builder envision the humans as a kind of aristocracy, superior to the robots they control. As is the case in all feudal societies, eventually the peasants or slaves revolt and murder their masters.