In Western music, a symbol that specifies a subdivision of pulses into relatively small metrical units. Each subdivision is called a measure and contains a fixed number of beats (Thaut 2008, p. 8). A time signature is given as two numbers; the first or top number gives the number of beats per measure, and the second or lower number indicates the type of note that is equivalent to one beat.
Jonathan Kramer asserts that a regular meter of the sort that a time signature creates is a reminder, within music, of “profane time”: the time that clocks can objectively measure. Kramer also observes that the important of metrical reularity has diminished during the 20th century (Kramer 1988, p. 17).