The yo-yo is believed to have originated in ancient China. It is a small round object consisting of two equally sized discs connected by an axle. The axle has a short string wound around it. To play, the string's free end is tied around the middle finger, the yo-yo is then grasped and thrown using a smooth motion. As the axle spins within the loop, a gyroscopic effect occurs, allowing time to perform a number of movements known as tricks. The yo-yo requires a great deal of skill and expertise to be played with in this manner. Competitions and championships are held all over the world.