When it would be more appropriate to use a pie chart instead of a line graph to show data?

A pie chart is more appropriate when you want to illustrate the proportional relationships of parts to a whole, particularly when displaying categorical data with limited segments. It visually emphasizes the relative sizes of each category, making it easier to see which categories dominate. In contrast, a line graph is better suited for showing trends over time, especially with continuous data. Thus, if the focus is on showing composition rather than trends, a pie chart would be the preferred choice.