This document provides an overview of several theories in ethics including utilitarianism, rights, justice, and egoism. It discusses each theory in 2-3 sentences and provides examples. Utilitarianism holds that an action is right if it produces the greatest good for the greatest number. Rights theory focuses on respecting people's entitlements and acting toward others as equals. Justice examines fair distribution of benefits and burdens among groups. Egoism asserts one should act in their self-interest or rational self-interest. The document compares the different theories and discusses some limitations and objections to certain approaches.