A radar chart compares multiple variables by arranging axes radially and connecting values into a polygon. It is also called a spider chart or web chart. It is often used to compare attributes of products, people, organizations, or performance profiles.

Historical Background

Early forms appeared in nineteenth-century statistical graphics and were later used in military, industrial, and educational assessment. Software such as Excel, Tableau, matplotlib, and Plotly made radar charts easy to create.

Design Notes

• Use a small number of variables.
• Keep axis scales consistent and meaningful.
• Avoid comparing too many polygons.
• Consider small multiples or bar charts for precise comparison.

Summary

Radar charts are useful for profile-like comparisons, but they can be hard to read precisely. They work best when the overall shape is more important than exact values.