A big machine is a machine with a large size or scope, used to achieve certain tasks or processes that would take a very long time to complete without automation. They have increased productivity by replacing physical labour and are often used in industry, agriculture and manufacturing. Examples include cranes, bulldozers, excavators and tractors. Big machines are usually powered by diesel engines or electric motors, although other forms of propulsion, such as solar or wind power, have been developed. They come in a wide range of shapes and sizes to suit different applications.
