Real tennis, often called "the sport of kings," is the original racquet sport from which modern lawn tennis derives, and is known as court tennis in the US and royal tennis in the UK and Australia. The term "real" was coined by journalists in the early 20th century as a retronym to distinguish it from the newer lawn tennis. Today, the sport is played on 45 active courts worldwide, primarily in the UK, Australia, the US, and France. The game uses handmade, cork-cored balls that are heavier and less bouncy than lawn tennis balls, with covers replaced every few weeks. Players use short, asymmetrical wooden racquets with tight nylon strings, most of which are produced by Grays of Cambridge. These unique equipment characteristics make real tennis a fast, precise game that emphasizes accuracy over power.