An electric guitar is a type of guitar that uses pickups to convert the vibration of its steel-cored strings into electrical current, which is then amplified. The signal that comes from the guitar is often electrically altered to achieve various tonal effects prior to being fed into an amplifier, which produces the final sound which can be either an electrical sound or an acoustic sound. Despite its traditional association with rock music, the electric guitar has long been used in many popular styles of music, including almost all genres of rock and roll, country music, jazz, blues, ambient (or "new-age"), and even contemporary classical music. The instrument's distinctive sound and intimate connection with many legendary internationally-famous musicians has made it the signature instrument of late twentieth-century music.