Cotton gin is a machine for removing the seeds from cotton fibers. It is widely believed that the American inventor Eli Whitney produced the first cotton gin. However, simple cotton gins were first used in India during ancient times. A version of these gins, the roller gin, had reached the American Colonies by the 1740's. In 1793, Whitney invented a faster, more economical way of separating cottonseeds from the fibers. His cotton gin helped make the United States the world's leading cotton grower.