A guitar string is a thin, elongated piece of material, typically made from metal or nylon, that vibrates to produce sound when plucked or strummed. Each string is attached to the guitar's body and neck, and they come in various thicknesses, known as gauges, which affect the tone and playability of the instrument. Guitar strings are categorized into different types, such as steel strings for acoustic guitars and nylon strings for classical guitars. The choice of string type can influence the overall sound, feel, and style of music played on the guitar, making it an essential component for musicians.