What is the function of barline?

A barline is a vertical line on a musical staff that divides the music into measures or bars, helping to organize the rhythm and structure of a piece. It indicates the end of a measure, allowing musicians to easily read and interpret the timing and grouping of notes. Barlines can vary in style, such as single, double, or repeat, each serving specific purposes in musical notation. Overall, they are essential for maintaining the flow and coherence of a musical composition.