A Venn diagram uses overlapping circles to show relationships between sets. It’s best suited for illustrating the similarities, differences, and intersections between 2 to 4 datasets.
For instance, in marketing, a Venn diagram might be used to identify customers who opened emails, clicked links, and made purchases. The overlapping areas represent users who performed multiple actions. The clear visual segmentation helps with understanding behavior overlaps.
Though intuitive and widely recognized, Venn diagrams become difficult to interpret with more than four sets. For more complex intersections, the Upset diagram is often a better alternative.