Classical guitar strings
From Wikipedia, the free encyclopedia
Classical guitar strings are strings manufactured for use on classical guitars. While steel-string acoustic guitar strings and electric guitar strings are made of metal, modern classical guitar strings are made of nylon and nylon wound with wire, which produces a different sound to the metal strings. Classical guitar strings were originally made with animal intestine and silk wound with animal intestine up until World War II, when war restrictions led Albert Augustine Ltd. to develop nylon strings. Nylon guitar strings were put into production in 1948. Strings made from fluorocarbon polymers have since been developed and are the main alternative to nylon strings.
Traditional

The three treble guitar strings (the three highest-pitched strings) are made from sheep or cow intestine, referred to as plain gut, while the three bass strings are made of a silk thread core wound with gut.
Modern
Since the development of nylon guitar strings by Albert Augustine Ltd. in 1948, the three treble strings are a single nylon filament, while the three bass strings are made of a core of fine nylon threadlike filaments wound with silver-plated bronze or copper wire.