A fretless bass is a type of electric bass guitar that does not have frets, which are the metal strips found on the fingerboard of traditional bass guitars. This design allows for a smoother, continuous surface, enabling players to slide between notes and create a unique sound. Fretless basses are often used in genres like jazz, funk, and world music, where expressive playing is essential. Playing a fretless bass requires a good ear and precise finger placement, as there are no frets to guide the player. Notable musicians, such as Jaco Pastorius, have popularized the instrument, showcasing its versatility and expressive capabilities. Fretless basses can produce a warm, rich tone that adds depth to musical compositions.