Music-score markings, such as clefs, are symbols used in musical notation to indicate the pitch of written notes. Clefs are typically placed at the beginning of a line of musical notation and are used to identify the pitch of the notes written on that line. Common clefs include the treble clef, bass clef, alto clef, and tenor clef. The treble clef is used for higher pitched instruments, such as the violin, while the bass clef is used for lower pitched instruments, such as the cello. The alto clef is used for middle-range instruments, such as the viola, and the tenor clef is used for instruments with a range between the treble and bass clefs, such as the trombone.