# Music Theory/How to read Music

This Wikibook is here to give the reader an idea of how to read music; however, this is not to say that this book will teach you to read music correctly. Neither will it teach you to play a musical instrument. Most music related subjects (and most other subjects for that matter) really ought to be studied under a teacher. If you do not want to hire a teacher then this should give you a general idea of how to read music.

## Staff

The staff is what every other symbol of musical notation is written on. It consists of 5 lines and 4 spaces that are used to identify which note is meant to be played based on which clef is shown at the beginning of the staff. When a note is too high or too low to be written on one of the lines or spaces (such as Middle C), smaller lines must be written above or below the staff, called "ledger lines".

## Clefs

The two most commonly used clefs are the treble clef and a bass clef.
The clefs determine what pitch the notes should fall on; for instance, the treble clef is a G-clef, so wherever the clef ends on is the note G. In the case of treble clef, it is the second line up from the bottom (the end of the clef wraps around the line). The bass clef is an F-clef, so the line between the two dots is the note F. Instruments that use the treble clef include the flute, trumpet, all the saxophones, all the clarinets, guitar (except for the bass), violin, and several others. The bass clef is used for instruments like the bassoon, bass guitar, cello, tuba, and trombone.
For the treble clef, a common mnemonic used to remember which notes correspond to each position would be "Every Good Boy Does Fine" for the notes on the lines (from bottom to top), and "FACE" for notes in the spaces between the lines (from bottom to top). It should be noted that other mnemonics exist, such as "Every Good Bird Does Fly", among others.
Another common mnemonic exists for the bass clef; "All Cows Eat Grass" to remember the notes in the spaces between the lines (bottom to top), and "Good Boys Do Fine Always". Similar to that of the treble clef, there are many such mnemonics, and one is welcome to invent their own to aid themselves should they see fit.
However, it should be noted that these clefs are not the only clefs in existence, with other clefs such as the alto clef and the tenor clef, both using the C-clef, suboctave and sopranino clefs, both using a derivative of the G-clef, or neutral clefs (used in percussion sheet music).

## Time Signature

A time signature is usually written as two numbers (one on top of the other) at the beginning of a piece that divides the piece into smaller bits called measures. These make it easier to read and provide hints as to which notes in each measure should be stressed. Measures are broken up using vertical lines that extend from the top line to the bottom line. The top number signifies how many beats each measure will contain, and the bottom note sets down which note will take the value of one beat; so, in 4/4 time, there are four beats in a measure and a quarter note will get one beat. Hence, there will be a time value equal to four quarter notes in every measure. The most common time signatures are 4/4, 3/4, 6/8, and 2/4.
Occasionally, there maybe be more than one time signatures denoted (with the time signatures following the second usually being written in brackets). This denotes that the time signature alternates between those time signatures in that order. For example, the figure on the left shows four measures, with the first and third measures being in 4/4 time and the second and fourth measures being in 3/4 time.
Sometimes, for ease of reading and counting, an odd time signature (time signature where the numerator does not divide into 2 or 3) may be represented as a compound time signature, with two or more separate time signatures joined with a plus sign, with the option of having multiple numbers on top per time signature also joined with a plus sign. For example, the figure on the left shows two measures in 5/4 time, except that the beats are split into 6 eighth notes (6/8 time) and 2 quarter notes (2/4 time). This compound meter is used in the theme of Mission: Impossible.

### Counting

When reading music, you also would need to know how to count, so as to be able to effectively communicate with fellow musicians. The system for counting is relatively simple. For each beat, count upwards numerically (i.e. 1, 2, 3, etc. with 7 being read "sev" to keep everything in one syllable). So two measures of 3/4 time could be counted as "1, 2, 3, 1, 2, 3". If a beat is subdivided into halves, the second subdivided beat is counted as "and" (written as an ampersand "&"). So the same two measures of 3/4 time subdivided into eighth notes (this type of metric modulation is called "double time") would be counted "1 & 2 & 3 & 1 & 2 & 3 &". If a beat is subdivided into thirds, the second and third subdivided beats are counted as "and" and "a" respectively (written "& a"). So the same two measures of 3/4 time subdivided into triplet eighth notes would be counted "1 & a 2 & a 3 & a 1 & a 2 & a 3 & a". Lastly, if a beat is subdivided into quarters, the second, third and fourth subdivided beats are counted as "e", "and" and "a" respectively (written "e & a"). So the same two measures of 3/4 time subdivided into sixteenth notes would be counted "1 e & a 2 e & a 3 e & a" repeated twice. For subdivisions in the reverse direction, one would simply count the beats after dividing them, so a measure of 4/4 time in half time would be counted as "1, 2". If there are further subdivisions beyond quartering the beat, musicians would usually count the beats as if they were metrically modulated so a measure of 2/4 time in octuple time would be counted as "1 e & a 2 e & a 3 e & a 4 e & a" repeated twice (assuming the direction is to count the measure as a compound meter of 8 + 8). For odd subdivisions (not group-able into groups of 2 or 3 beats), the method of counting would depend on the grouping and tempo. For example, if one needs to count 5 eighth notes and the tempo is very slow, one might simply count it as "1, 2, 3, 4, 5". But if the tempo were too fast to count it in that manner, one might count it as "1 e & a &", or "1 & a 2 &" if the direction is to group it as beats of 3 + 2. However, at a very fast tempo, there may be little merit in counting tuplets this way.
As such, one is able to use these counting terms to refer to specific beats in a measure. For instance, in the excerpt of music on the right, one might say that the second high C in the second measure of the passage is the "a of beat 4".

## Note and Rest Durations

The notes and rests on a staff show the duration of a sound or a pause in the music. There are several different time values of notes and rests; the most basic of which are the whole note (also called semibreve) and rest, each having 4 beats:
The half note (also called minim) and rest, each being half as long as a whole note:
The quarter note (also called crochet) and rest, each being one-quarter the length of the whole note and half the length of a half note:
The eighth note (also called quaver) and rest, each being one-eighth the length of the whole note and half the length of a quarter note:
The sixteenth note (also called semiquaver) and rest, each being one-sixteenth the length of the whole note and half the length of an eighth note:
And so forth with each increasing division getting one extra "flag."
Of course, there are other types of notes, like the breve or the longa, but those aren't as common as these few.

### Dotted Notes

Sometimes, note heads may have dots beside them, which denotes that the length of the note is one and a half of its original length. So for instance, a dotted quarter note would have the same note length as a quarter note and an eighth note. Notes can have more than one dots, with the value of the note being modified recursively. For instance, a double dotted quarter note would have the same note length as a quarter note and a dotted eighth note, or a quarter note, an eighth note and a sixteenth note (notice how the "dot" of the quarter note, i.e. the eighth note has become dotted).