A bubble chart builds on a scatter plot by adding a third variable, typically represented by the size of the bubble. This allows three dimensions of data to be displayed at once: position on the x-axis, position on the y-axis, and magnitude via bubble size.
For example, a company may want to compare product categories based on profitability (x-axis), sales volume (y-axis), and customer satisfaction score (bubble size). This rich multidimensional view allows decision-makers to identify which products are performing well across several KPIs simultaneously.
Bubble charts are often used in market analysis and strategy.