A score is a set of instructions written in music notation or other symbols and gestures to enable a person or ensemble to perform a piece of music. Most scores use an array of conventional symbols and words to convey the pitch, duration, volume, and attack with which notes are created, making it possible for a piece of music, as conceived by a composer, to be performed with a fair amount of similarity by ensembles with any culture and background.
The conventions for musical scores include the following:
• A conductor’s score shows the entire scope of the piece, while scores for individual players, called parts, show only their individual lines, sometimes including cues, which are bits of music from other players that are given to help the performer identify what is going on while he is not playing, especially after a large number of bars of rests.
• The main focus of a score is a set of musical staves consisting of five horizontal lines and the spaces between them, which represent specific pitches, which differ depending on which clef — usually treble, bass, alto, and tenor — is designated. On the musical staff or stave, a note place higher has a higher pitch, while a note placed lower on the staff has a lower pitch. Extensions called ledger lines are used to extend beyond the five lines of the staff in order to show very high and very low pitches.
• Very often a key signature is placed at the beginning of the staff to designate the scale, or set of notes, that will be used in the piece. The key signature can change during the piece or a key signature can be omitted in a piece that does not stick to a particular major or minor scale. In addition, accidentals can be used to shift individual notes to include pitches that are not within the scale shown by the key signature.
• A time signature showing the meter of the piece — how many beats in a bar and which note duration gets one beat — is also generally placed at the beginning of the first staff. Like the key signature, the time signature can change during the piece.
• A tempo indication at the beginning of the score indicates the pace at which the piece is to be played. Like the key signature and time signature, the tempo can also change.
• Notes to indicate sounds and rests to indicate silence are combined on the staff as needed. They are made with symbols that indicate a variety of durations, and while the symbols are pretty universally understood, the names for them are distinct in American and British English.
• Dynamics over or under the notes are indicate with words, abbreviations, and a variety of lines. They let the performer know the volume with which the notes should be played. Dynamics change frequently in most scores.
• The entire score is organized with time flowing from left to right and, on a conductor’s score, the staves of all instruments that are playing at a particular time grouped into a system. By looking from the top to the bottom of the score at any given point, you can see what every instrument is doing at that moment. By looking from left to right along one instrument’s staff, you can see what that instrument does through the entire duration of the piece.
• The order of instruments in a conductor’s score is also traditional, but depends on the ensemble and whether there is a soloist or vocalists involved. In a standard orchestral score, the top grouping is the woodwinds. This is followed by the brass, then the percussion, and the strings are placed at the bottom of the score.
Although these conventions are adapted and altered as needed, their general use means that anyone picking up a score has an immediate sense of how to understand it.