Metric

Meter or metre is a concept related to an underlying division of time characteristic of western music. The concept provides that the pattern, is usually 2, 3, or 4 beats long, (duple, triple, quadruple), and each beat may be normally divided into 2 or 3 basic subdivisions (simple, compound). Another view is that meter is the measurement of a musical line into measures of stressed and unstressed "beats", indicated in Western music notation by a symbol called a time signature. Yet another view is that "meter" describes the whole concept of measuring rhythmic units, but it can also be used as a specific descriptor for a measurement of an individual piece as represented by the time signature—for example, "This piece is in 4/4 meter(help·info)" is equivalent to "This piece is in 4/4 time" or "This piece has a 4/4 time signature" – all of which are formally called simple quadruple meter, four beats, each normally divided by 2.   Wikipedia