axle can be either a fixed axle or a bearing axle. The former does not spin, while the latter variety spins in one direction. Noticeable differences between the two include friction involved, the amount of time the diabolo can spin for, and tension. There are also certain tricks that are only possible with one type of axle. Basic principles The most basic act of diabolo manipulation is to spin it on the string. "The string is placed between the circles, but in order for the diabolo to balance, it must maintain a spinning motion, much like a yo-yo." However, "considerably more skill is needed to twirl a diabolo...than the Yo-yo it resembles." "Diabolo requires hard practice and highly developed skills" Typically, the player pulls the stick in his or her dominant hand so that the string moves along the axle, turning it. "The player...swing[s] the string right and left." By doing this repeatedly and rapidly the diabolo rotates faster. The diabolo spin can be accelerated more quickly using various methods: the 'whip' rotates the diabolo faster by moving one handstick in front of the user's body and past the other handstick, the 'wrap' rotates the diabolo faster when the user wraps a loop of the string around the axle. Both methods increase the amount of string contact with the axle in any given time. Once spin speed is increased to a sufficient level that the diabolo is stable, the user can then perform tricks. "Skillful players can set it whirling at a rate of 2,000 revolutions a minute, it is said." Depending on how long a trick takes to perform, the user will normally have to spend some time increasing the spin speed of the diabolo before performing other tricks. Skilled users can perform multiple tricks while maintaining the spin speed of the diabolo. "A skilled person [can] catch it, hurl it fifty or sixty feet into the air, then catch it again with little effort." Tricks and styles Fundamental tricks Advanced tricks There are countless tricks and variations that fall outside the above categories; these are often more difficult and form the cutting edge of modern diabolo routines. Some examples are: Multiple diabolos Perhaps the most active area of development for diabolo performance involves tricks with more than one diabolo on a single string. When manipulating multiple diabolos "low", the diabolos orbit continuously on the string in a "shuffle".