Political philosophy is a branch of philosophy that examines the concepts and principles underlying political systems, institutions, and practices. It explores questions related to the nature of government, authority, justice, rights, freedom, and democracy, among others. Political philosophers seek to understand and evaluate different forms of government, ideologies, and policies, and often aim to inform and improve political decision-making and governance. Key figures in the history of political philosophy include Plato, Aristotle, Machiavelli, Hobbes, Locke, Rousseau, Marx, and Rawls.