bar line

music

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Last updated

June 18, 2026

Quick Summary

In music, bar lines are vertical lines that divide the staff into measures, which are segments of time. These divisions help organize rhythm and timing within a piece of music. A double bar, consisting of two adjacent vertical lines or a heavy single line, is used to separate principal sections of a musical composition. The grouping of beats into regular measures is called metre, and each measure is set off by bar lines. The time signature at the beginning of a piece indicates the number of beats in a measure and the value of the basic beat.123

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rhythm
Time
…15th century have they been indicated by means of bar lines. Thus, the terms measure and bar are often used interchangeably.
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…15th century have they been indicated by means of bar lines. Thus, the terms measure and bar are often used interchangeably.
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musical notation
Tempo and duration
…achieved by two devices: the bar line and the time signature. The bar line primarily indicates a point of main stress. Bar lines are usually equally spaced as to duration, though there are numerous exceptions. A time signature indicates, first, the duration of the space between two bar lines (a…
Read More
…achieved by two devices: the bar line and the time signature. The bar line primarily indicates a point of main stress. Bar lines are usually equally spaced as to duration, though there are numerous exceptions. A time signature indicates, first, the duration of the space between two bar lines (a…
Read More

rhythm
Time
…been indicated by means of bar lines. Thus, the terms measure and bar are often used interchangeably.
Read More
…been indicated by means of bar lines. Thus, the terms measure and bar are often used interchangeably.
Read More