What are the key differences between a monarchy and an oligarchy in terms of power distribution and governance?

In a monarchy, power is held by a single ruler, usually a king or queen, who inherits their position. In an oligarchy, power is held by a small group of people, often wealthy or influential individuals. Monarchies tend to have centralized power and are often hereditary, while oligarchies have power distributed among a select few who may or may not be elected. Monarchies typically have a more hierarchical governance structure, while oligarchies may have a more decentralized or informal power structure.