Background and Identification
A yo-yo—often spelled “yoyo”—is a seemingly simple toy made from two disks which are joined at the center by some kind of axle. A string is attached to the axle and wound up so that when you throw a yo-yo down, the string unwraps and then wraps back up again as the yoyo “climbs” back up the string to your hand. The yo-yo was likely invented in China and spread to other countries like the Philippines, where the word “yo-yo” is said to originate. Some of the earliest records of the yo-yo come from Ancient Greece, where records show that children played with yo-yos made from wood, metal, or terracotta. This pottery cup, dated to 440 B.C.E. in Greece shows a boy playing with a yo-yo.
The design of yo-yos progressed significantly through the 1900s, with a major change coming through the work of Pedro Flores and his Yo-Yo Manufacturing company in the late 1920s. While most older yo-yos use a string tied directly to the axle of the yo-yo with a knot, yo-yos designed by Flores used a technique common in the Philippines where the yo-yo string is made from a extra-long piece of string that is folded in half and twisted to make a loop in the center. This looped design allows the yo-yo to spin freely at the bottom of the string, a basic yo-yo trick called “sleeping.” In contrast, an older yo-yo would return to your hand automatically without the ability to sleep. More recently, some yo-yos have been manufactured with ball bearings inside that allow the axle to rotate and reduce the friction created by the string rubbing against the yo-yo axle.
The most common issue with a yo-yo is the need for a new string because your current one is frayed or has snapped. Luckily, yo-yo strings are cheap and you can find an excellent guide for restringing a yo-yo here on iFixit.
YoYoExpert.com has a variety of maintenance tips for other common yo-yo issues. For more detailed instructions specific to your yo-yo, you can usually find the model of your yo-yo by looking on the side of one of the disks for identifying information such as the brand and model.