The grand staff (also called the "great staff" or "grand stave" or "grand stave") is used in music notation when more than one note across several octaves may be played at once. It's most commonly seen in piano music.
A grand staff is drawn as two staffs, each with their own clef, connected at the left edge by a vertical line and a bracket. In piano music, the right hand follows the top staff (treble clef) and the left hand follows the bottom staff (bass clef). Middle C lies one line below the top staff and one line above the bottom staff.
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