Staff (music)

In Western musical notation, the staff (UK also stave; plural: staffs or staves), also occasionally referred to as a pentagram, is a set of five horizontal lines and four spaces that each represent a different musical pitch or in the case of a percussion staff, different percussion instruments. Appropriate music symbols, depending on the intended effect, are placed on the staff according to their corresponding pitch or function. Musical notes are placed by pitch, percussion notes are placed by instrument, and rests and other symbols are placed by convention.

The absolute pitch of each line of a non-percussive staff is indicated by the placement of a clef symbol at the appropriate vertical position on the left-hand side of the staff (possibly modified by conventions for specific instruments). For example, the treble clef, also known as the G clef, is placed on the second line (counting upward), fixing that line as the pitch first G above "middle C".

The lines and spaces are numbered from bottom to top; the bottom line is the first line and the top line is the fifth line.

The musical staff is analogous to a mathematical graph of pitch with respect to time. Pitches of notes are given by their vertical position on the staff and notes are played from left to right. Unlike a graph, however, the number of semitones represented by a vertical step from a line to an adjacent space depends on the key, and the exact timing of the beginning of each note is not directly proportional to its horizontal position; rather, exact timing is encoded by the musical symbol chosen for each note in addition to the tempo.

A time signature to the right of the clef indicates the relationship between timing counts and note symbols, while bar lines group notes on the staff into measures.

Staff is more common than stave in both American English and British English,^{[citation needed]}. with the latter being, in fact, a back-formation from the plural staves. The plural staffs also exists for staff in both American and British English, alongside the traditional plural staves. In addition to the pronunciations expected from the spellings, both plural forms are also pronounced /stævz/ in American English.

The vertical position of the notehead on the staff indicates which note to play: higher-pitched notes are marked higher on the staff. The notehead can be placed with its center intersecting a line (on a line) or in between the lines touching the lines above and below (in a space). Notes outside the range of the staff are placed on or between ledger lines—lines the width of the note they need to hold—added above or below the staff.

Which staff positions represent which notes is determined by a clef placed at the beginning of the staff. The clef identifies a particular line as a specific note, and all other notes are determined relative to that line. For example, the treble clef puts the G above middle C on the second line. The interval between adjacent staff positions is one step in the diatonic scale. Once fixed by a clef, the notes represented by the positions on the staff can be modified by the key signature or accidentals on individual notes. A clefless staff may be used to represent a set of percussion sounds; each line typically represents a different instrument.