In political science, a revolution is a fundamental and relatively sudden change in political power and political organization which occurs when the population revolts against the government, typically due to perceived oppression or political incompetence. In book V of the Politics, the Ancient Greek philosopher Aristotle described two types of political revolution:
Complete change from one constitution to another
Modification of an existing constitution.
Revolutions have occurred throughout human history and vary widely in terms of methods, duration and motivating ideology. Their results include major changes in culture, economy, and socio-political institutions, usually in response to perceived overwhelming autocracy or plutocracy.
Scholarly debates about what does and does not constitute a revolution center on several issues. Early studies of revolutions primarily analyzed events in European history from a psychological perspective, but more modern examinations include global events and incorporate perspectives from several social sciences, including sociology and political science.