A steam engine is a machine that converts the energy from steam into mechanical work. It works by heating water in a boiler until it turns into steam, which then expands and pushes against a piston. This movement can be used to turn wheels or drive machinery, making it a key invention during the Industrial Revolution. Steam engines played a crucial role in transportation, powering trains and boats. They allowed for faster travel and the movement of goods over long distances. The development of steam engines marked a significant advancement in technology, changing how people lived and worked.