Editing Rhythm (section)

===Metric structure===
{{Further|Metre (music)|Bar (music)|Metre (poetry)}}

[[File:Claves-detail.gif|thumb|left|upright=1.35|Notation of a [[Clave (rhythm)|clave rhythm pattern]]: Each cell of the grid corresponds to a fixed duration of time with a resolution fine enough to capture the timing of the pattern, which may be counted as two bars of four beats in divisive (metrical or symmetrical) rhythm, each beat divided into two cells. The first bar of the pattern may also usefully be counted additively (in measured or [[asymmetrical rhythm]]) as {{serif|'''3 + 3 + 2'''}}.]]

The study of rhythm, stress, and [[pitch (music)|pitch]] in [[speech]] is called [[prosody (linguistics)|prosody]] (see also: [[prosody (music)]]): it is a topic in [[linguistics]] and [[poetics]], where it means the number of lines in a [[verse (poetry)|verse]], the number of syllables in each line and the arrangement of those syllables as long or short, accented or unaccented. Music inherited the term "[[Meter (music)|meter or metre]]" from the terminology of poetry.{{sfn|Scholes|1977b}}{{sfn|Scholes|1977c}}{{sfn|Latham|2002}})

The metric structure of music includes meter, tempo and all other rhythmic aspects that produce temporal regularity against which the foreground details or [[Duration (music)|durational patterns]] of the music are projected.{{sfn|Winold|1975|pp=209–210}} The terminology of western music is notoriously imprecise in this area.{{sfn|Scholes|1977b}} MacPherson preferred to speak of "time" and "rhythmic shape",{{sfn|MacPherson|1930|p=3}} [[Imogen Holst]] of "measured rhythm".{{sfn|Holst|1963|p=17}}

[[File:Phenakistoscope 3g07690d.gif|thumb|An [[Phenakistoscope|early moving picture]] demonstrates the [[waltz]], a dance in triple metre.]]

Dance music has instantly recognizable patterns of beats built upon a characteristic tempo and measure. The Imperial Society of Teachers of Dancing defines the [[Tango music|tango]], for example, as to be danced in {{music|time|2|4}} time at approximately 66 beats per minute. The basic slow step forwards or backwards, lasting for one beat, is called a "slow", so that a full "right–left" step is equal to one {{music|time|2|4}} measure.{{sfn|Imperial Society of Teachers of Dancing|1977|p={{Page needed|date=July 2014}}}} (''See [[Dance#Rhythm|Rhythm and dance]]''.)

[[File:clavepattern.svg|thumb|right|upright=1.35|Notation of three measures of a clave pattern preceded by one measure of steady quarter notes. This pattern is noted in [[double time]] relative to the one above, in one instead of two four-beat measures.[[File:Clave pattern.ogg|thumb|none|Four beats followed by three clave patterns]]]]

The general classifications of ''metrical rhythm'', ''measured rhythm'', and ''free rhythm'' may be distinguished.{{sfn|Cooper|1973|p=30}} Metrical or divisive rhythm, by far the most common in Western music calculates each time value as a multiple or fraction of the beat. Normal accents re-occur regularly providing systematical grouping (measures). Measured rhythm ([[additive rhythm]]) also calculates each time value as a multiple or fraction of a specified time unit but the accents do not recur regularly within the cycle. Free rhythm is where there is neither,{{sfn|Cooper|1973|p=30}} such as in Christian [[chant]], which has a basic pulse but a freer rhythm, like the rhythm of prose compared to that of verse.{{sfn|Scholes|1977c}} ''See [[Free time (music)]]''.

Finally some music, such as some graphically scored works since the 1950s and non-European music such as [[Honkyoku]] repertoire for [[shakuhachi]], may be considered ''ametric''.{{sfn|Karpinski|2000|p=19}} ''Senza misura'' is an Italian musical term for "without meter", meaning to play without a beat, using time to measure how long it will take to play the bar.{{sfn|Forney and Machlis|2007|p={{Page needed|date=December 2009}}}}