Ethical theories are systematic approaches to understanding what is right and wrong. They provide frameworks for evaluating moral dilemmas and guiding behavior. Common ethical theories include utilitarianism, which focuses on the greatest good for the greatest number, and deontology, which emphasizes duties and rules regardless of the consequences. Another important ethical theory is virtue ethics, which centers on the character and virtues of individuals rather than specific actions. Each theory offers different perspectives on morality, helping individuals and societies navigate complex ethical issues and make informed decisions.