A guitar player has several alternative notational systems available: tablature, chord symbols, chord boxes and various forms of shorthand. Each has its strengths, but also its weaknesses. The main weakness is that tablature and chord boxes are idiosyncratic to the guitar and require knowledge of how the guitar is constructed and tuned. Furthermore, tablature only specifies which frets and strings to play, it is difficult to notate rhythm, the relative duration of notes. Therefore, these alternative notational systems are at best memory aids.
Staff notation solves both these problems in one go. It is a self-contained notational system where you can notate pitch, duration, articulation, dynamics and many other aspects of music. It is also universal and has been relatively unchanged for hundreds of years: you can easily pick up one of Bach's original manuscripts and play from it, just as a musician in the year 2310 will likely (hopefully?) be able to play from your manuscript.
This article is to be considered as constantly under construction. Omissions are to be regarded as me not having got there yet.
The most basic part of musical notation is the staff, which is a collection of five lines with four spaces in-between:
Notes are placed on any of the lines, or in any of the spaces, including on the edges of the staff:
Notes are played from left to right; if two notes occupy the same vertical space they are to be played simultaneously. Lower notes are placed towards the bottom of the staff, higher notes towards the top.
If the staff isn't wide enough, temporary lines and spaces can be placed outside of the staff proper; these are called ledger lines:
The relative pitches of notes are established by putting what's called a clef at the start of each staff. A clef fixes a certain pitch to the line where it is placed. There are three kinds of clefs:
The G clef fixes the position of middle G, the F clef bass F and the C clef middle C. Clefs can be positioned on any line, but the common practice is to center the G clef on the second line (treble clef), the F clef on the fourth line (bass clef), and the C clef on either the third (alto clef) or fourth line (tenor clef):
Here are examples of middle C using the four clefs:
Alternate clefs may appear at any time in written music, most often for longer passages that would be notated with too many ledger lines for easy reading.
In certain types of scores, most usually vocal music, clefs can be transposed, i.e. the notes sound an octave lower or higher than notated. Instead of writing 8va or 8vb throughout the entire piece, an 8 is added to the clef. If the 8 is added below the clef, the notes sound one octave below written, and vice versa.
Transposing instruments are never written with transposing clefs.
Staff notation is not tied to any particular temperament or tuning, nor are the notes, even those fixed by clefs, tied to any particular pitches. Therefore, it has been decreed by international standard (ISO 16:1975) that middle A, i.e. the A above middle C, should sound at 440 Hz.
Notes and Beams
Notes take on various shapes depending on their relative duration. Notes fall in an exact 1:2 ratio to the next shorter and longer note values, so that a whole-note equals two half-notes equals four quarter-notes and so on.
- The whole note is written as an oval.
- The half note adds a stem.
- The quarter note has a solid note-head.
- The eighth note adds a flag to the stem.
- Further subdivisions (16, 32, 64 etc.) add progressively more flags.
I use American terminology (hopefully) consistently. In British parlance, note values have different names, stemming from mensural notation, the medieval precursor to traditional music notation:
Stems point upwards on notes up to and including the second space, downwards from and including the third space. Notes on the center line can point either way:
Flags can be tied together as beams, with the majority determining the orientation:
Ties and Dots
To lengthen a note, it can be tied to the next note, thereby adding their time values. This second note is not struck. The two tied half-notes in the following example are exactly equivalent to a whole-note:
Dotting a note is the same thing as tying it with a note of half its time value (1 + 1/2). This can be extended by double- (1 + 1/2 + 1/4) or even triple-dotting (1 + 1/2 + 1/4 + 1/8):
There is no rule that says when one should use ties or dots, but a dotted note may not extend across a bar line, a tie must be used:
Tuplets are divisions of a note that fall outside the normal 1:2 ratio. The most common variety of tuplet is the triplet, which has 2/3 the time value of a regular note. Hence, three triplets occupy the same space as two regular notes of the same value:
Unflagged and -beamed notes use a bracket, whereas beamed notes simply put the number over the beam to indicate tuplets. In printed music, in long passages played solely with triplets, the number may be omitted after a measure or so.
Uneven tuplet numbers are considered to be played against the next smaller factor of 2. E.g. 5 notes are played against 4, 7 also against 4 but 9 against 8. Even numbers often mean lengthening of beats in triple or compound meters, which can alternately be expressed by ties or dots.
Rests are instructions not to play and follow the same basic principles of subdivision as notes. Note how the flags on the 1/8- through 1/64 rests correspond to those of the 1/8- through 1/64-notes:
A whole-note rest can be used as a general one-measure rest (irrespective of time signature). Rests cannot be tied, but they can be dotted. They also cannot extend past the bar line, a new rest symbol is needed in that case.
Staff notation contains spaces for the natural notes: C, D, E, F, G, A and B. Enharmonic notes are notated with accidentals: flat, sharp, double-flat, double-sharp and cancelled with the natural sign, as shown below:
An accidental applies to all notes on that line or space until the next bar line, unless cancelled by a natural sign:
- Measure 1: B natural – B flat – B flat. The accidental on the second note applies on all notes occuying that line/space until the next bar line.
- Measure 2: B natural – B flat – B natural. The bar line immediately preceding the cancels whatever accidentals might have been used during measure 1. The third note is preceded by a natural sign, which cancels previous accidentals on that line/space.
- Measure 3: B flat – B natural – B flat. The second note is B natural, because accidentals only apply to one line/space. That's also why the accidental is needed to make the third note a B flat.
- Measure 4: B natural – B double-flat – B flat. The double-flat is partially cancelled by a combination natural/flat accidental.
The relative keys of C major and A minor require no enharmonic notes, hence there are no sharps or flats on the staff. All other keys require the use of one or more sharps or flats; the following is a passage in E major:
This can quite obviously get rather unwieldy. However, there is a way around it. You simply take all the required accidentals and put them at the start of each staff:
The two preceding examples are exactly equivalent—but which would you rather sight-read?
The collection of accidentals at the start of the staff is called the key signature. These accidentals apply throughout the piece unless temporarily cancelled by other accidentals:
In the preceding example, the first three notes are all F sharps, because the key signature applies to all occurrences of F and not just the line where it is placed. The second measure contains three F naturals—note how individual natural signs are required, because an accidental only applies to the one line/space.
Accidentals can occur in spite of a key signature, even on the spaces/lines that are affected by the key signature. These are called cautionary accidentals are can be used to clarify potentially ambiguous situations:
Accidentals are not cumulative, which is why in the preceding example, the F sharp in the second measure is not an F double-sharp.
Temporary modulations to other keys are usually written with accidentals, but permanent or more wide-ranging modulations might be aided by a new key signature in the middle of the piece. In such cases, a double bar line is written, followed by the new key signature. If the new key signature contains fewer sharps or flats, natural signs are used to cancel the unneeded signs:
Here are the key signatures for 15 major keys and their relative minor keys:
|B flat major
|E flat major
F sharp minor
|A flat major
C sharp minor
|D flat major
B flat minor
G sharp minor
|G flat major
E flat minor
|F sharp major|
D sharp minor
|C flat major
A flat minor
|C sharp major|
A sharp minor
The keys with seven accidentals in the key signature are seldom seen because they're enharmonically equivalent to other keys that use fewer accidentals. C sharp major (7 sharps) equals D flat major (5 flats) and C flat major (7 flats) equals B major (5 sharps). G flat and F sharp both use six accidentals, so there it's either way.
In other clefs, key signatures are written as follows, making sure that no accidental is placed on a ledger line:
Tempo and Time Signature
In music notation, measures (or bars) are indicated by vertical thin lines:
The length of each measure is indicated at the start of the piece by the time signature. The bottom number indicates which note value is the basic note value of the beat, the top number tells us how many such notes are to be played per measure.
In the above example, the time signature means that each measure must be filled out by notes equalling the value of two quarter notes (2/4 = 2 x 1/4).
4/4 time is also known as common time and is frequently simplified into the symbol C: 
2/2 time, or alla breve time, has a similar symbol with a strikethrough:
The absolute time values of notes are defined by setting the tempo. Traditionally, tempi are expressed using Italian words, e.g. Allegro (fast), Andante (slowish, lit. "walking"), Presto (really fast) or Adagio (really slowly).
The tempo can also be specified in more detail by stating the note value indicated in the time signature and how many such beats should occur per minute (BPM: beats per minute).
In compound triple meters, the beat is often felt on a higher note value, so in such meters, the metronome mark is specified using a dotted note of the next longer note value. For example, in 6/8, 9/8 and 12/8 time, the tempo is often set against a dotted quarter note.
Guidelines for Notating
In addition to the above, there are general guidelines for notating music. Unless a certain effect is sought, they can be summarized quite easily: no unnecessary complication. Music notation is supposed to be quick and easy to write and unambiguous to interpret, especially on the fly.
Correct spelling is important. Notes have many names (35 names for 12 notes!) in order to make them fit in widely different contexts. A G might be notated as an F double-sharp as a leading-note in G sharp minor:
An A might be renotated as a B double-flat in a diminished seventh chord resolving into an A flat triad:
An F is notated as an E sharp as a leading-note in F sharp minor and major:
Ties, Rests and Beams
Notes and rests should ideally not extend across beats (measure 1) unless the note picture becomes clearer by not tying (measure 2):
Beams should be used to group notes that belong to the same beat:
As the absolute durations of notes are determined by setting the tempo, it might be a relevant question why there are so many flavors of triple time: 3/2, 3/4, 3/8 and so on. Are these for different tempos?
Yes and no. In the old days, before the invention of the metronome, it was common practice to associate certain Italian tempo markings with certain note values as compared to the human heartbeat (60–80 bpm). Thus, in a slow tempo such as Adagio, one heartbeat might equal a quarter note, whereas it would equal a half note in a quicker tempo such as Allegro.
Nowadays, composers can set the tempo down to the last detail via electronic means. It is not necessary to associate certain base note values with certain tempi. The main principle of music notation can be a guiding principle: clarity. Fast passages in slow tempos can mean lots of flags and beams, which is why it can be important not to use too small base note values.