What racquet strings are made of?

Based on the source of material, racquet strings of tennis and badminton racquets can be categorized as natural and synthetic strings. As it has been proved that the properties like strength, density, tension and elasticity of different racquet strings could affect a player’s performance, it is important to know the source and properties of strings. The most commonly used type of strings with natural composition is natural gut. Animal intestines are made out of thin and long natural fiber which gives them high elasticity in peristaltic functions of digestion process. Therefore fiber isolated from the outermost layer of intestines (serosa) of animals like cattle are used in producing racquet strings. They are also known as catgut and are known as the most efficient type of strings. Among the synthetic types of racquet strings Nylon holds a greater popularity among beginner and amateur players for being the cheapest type. Nylon strings are available in two forms with only one filament or multiple filaments covered by a coating. Multi-filament Nylon strings are known as a cheaper substitute for catgut. There’s another type of soft multi-filament synthetic racquet string which are made with materials known as Zyex and polyolefin. Other string materials such as Zyex, Vectran, Polyester, Polyolefin and Kevlar have specific properties beneficial for the function of a racquet. For examples Zyex is known to have high rebound efficiency and stiffness similar to natural gut, Vectran and Polyester provide high durability and stiffness, Kevlar is the most durable string available, and Polyolefin strings are smooth and comfortable and commonly used as cross strings in hybrid. Therefore these types of strings are chosen by players with specific requirements and they differ from amateurs, beginners and experts. Though metal strings are not very abundantly used in modern times, in the past piano strings were also used to make racquets.