The Ups and Downs of yo-yos

the yo-yo is an object consisting  an axle conected to two disks and length of string looped around the axle.
There are many yo-yos tricks, like sleeper this is one the most basic tricks but the most famous tricks on the yo-yos is "Walk  the dog" this is done by throwing a strong sleeper and allowing the yo-yo to roll across the floor, before tugging it back to the hand.