Utilitarianism is an approach in ethics that tries to answer the question, ‘What should people do?’ It holds that the best action is one that makes the most people happy and causes the least amount of pain. It argues that when we make a decision, we should consider the consequences of our actions. We should add up all the good outcomes and subtract all the bad ones. When the good outweighs the bad, then that action is considered morally right. According to utilitarianism, everyone's happiness counts equally. It not just about making ourselves happy, but also about ensuring that our actions help others be happy. The goal is to create the maximum amount of happiness for the greatest number of people.

However, some critics argue that utilitarianism has certain problems. Firstly, it is hard to predict all the consequences of an action. Secondly, sometimes doing what makes the most people happy might not be fair to everyone. For example, if a town has to decide where to put a new garbage dump, it might make most of the people happy to put it in a poor neighbourhood, but that would not be fair to the people who live there.