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===Harmony===

===Harmony===

When two or more notes sound at the same time, it is called a chord, and the distance between the notes is the interval. In the western 12-note scale common usage, an interval is often expressed in relative terms, using the eight notes that make up an octave and prefixing 'major' or 'minor' to account for the interstitial notes. For instance, the interval between 'C' and 'E' is a 3rd because 'E' is the 3rd note in the major scale of C. One-half step below that is a minor 3rd, although this exact same note could also be called an augmented 2nd.

When two or more notes sound at the same time, it is called a [[chord (music)|chord]] , and the distance between the notes is the interval. In the western 12-note scale common usage, an interval is often expressed in relative terms, using the eight notes that make up an octave and prefixing 'major' or 'minor' to account for the interstitial notes. For instance, the interval between 'C' and 'E' is a 3rd because 'E' is the 3rd note in the major scale of C. One-half step below that is a minor 3rd, although this exact same note could also be called an augmented 2nd.

[[Harmony]] is the study of notes which occur together or which are perceived as being together. This usually means notes which are played simultaneously, as in a chord, but can also apply to notes within a melody which outline a chord. The harmony that results from the combination of any two or more notes depends on the interval present between those notes. A system of Roman numerals is the most common means used to analyse harmony.

[[Harmony]] is the study of notes which occur together or which are perceived as being together. This usually means notes which are played simultaneously, as in a chord, but can also apply to notes within a melody which outline a chord. The harmony that results from the combination of any two or more notes depends on the interval present between those notes. A system of Roman numerals is the most common means used to analyse harmony.

[[Image:In concert Jean Claude Gaugy.jpg|left|220px]]

[[Image:In concert Jean Claude Gaugy.jpg|left|220px]]

Many of the feelings and emotions that music can evoke are a result of the tension between the consonant (pleasant) sound of some intervals, and the dissonant sound of others. During the development of western music, certain rules were established for proper harmony, and these rules specified how intervals ([[chords]]) could change over time in the music.  

Many of the feelings and emotions that music can evoke are a result of the tension between the consonant (pleasant) sound of some intervals, and the dissonant sound of others. During the development of western music, certain rules were established for proper harmony, and these rules specified how intervals (chords) could change over time in the music.  

For example, the interval of the 3rd is one of the most common and consonant in classical (and popular) music. But in the medieval music, 3rd were deemed to be dissonant. While they still occurred, particularly in English music more than continental European music, they would 'resolve' to a 5th, which was considered a purer interval. In classical music, the open 5th is considered to sound too bare and exposed. Until the sixteenth century, chords containing certain intervals, like 7ths, were required to resolve to the more harmonious octave, while other intervals, like diminished 5ths, were deemed ugly and even considered evil, and banned from use in liturgic music. In fact, the diminished fifth (or augmented fourth) was referred to as the ''diabolus in musica'' (literally, 'the devil in music'), as was believed to represent Satan. Today, in writing counterpoint, students are taught not to write lines which leap between or outline the diminished fifth, although this is now for musical rather than superstitious reasons.

For example, the interval of the 3rd is one of the most common and consonant in classical (and popular) music. But in the medieval music, 3rd were deemed to be dissonant. While they still occurred, particularly in English music more than continental European music, they would 'resolve' to a 5th, which was considered a purer interval. In classical music, the open 5th is considered to sound too bare and exposed. Until the sixteenth century, chords containing certain intervals, like 7ths, were required to resolve to the more harmonious octave, while other intervals, like diminished 5ths, were deemed ugly and even considered evil, and banned from use in liturgical music. In fact, the diminished fifth (or augmented fourth) was referred to as the ''diabolus in musica'' (literally, 'the devil in music'), as was believed to represent Satan. Today, in writing counterpoint, students are taught not to write lines which leap between or outline the diminished fifth, although this is now for musical rather than superstitious reasons.

Throughout the classical and romantic eras, the harmonic language used by composers was gradually expanded, becoming increasingly complex and free. By the time of the early twentieth century, certain composers like Arnold Schoenberg broke away from traditional tonality entirely, and pioneered the use of atonal harmony.

Throughout the classical and romantic eras, the harmonic language used by composers was gradually expanded, becoming increasingly complex and free. By the time of the early twentieth century, certain composers like [[Arnold Schoenberg]] broke away from traditional tonality entirely, and pioneered the use of atonal harmony.

=== Rhythm ===

=== Rhythm ===