A Radar chart is like a spiderweb chart on which all the categories of an object are represented on different axes. The numeric-units distribute on different axes that help to plot the chart. After plotting data points of every axis, they join making a polygon.
Why do you need it?
When we have different characteristics on an object to display, we will use a bar chart, but when the number of categories is more, then it becomes complicated. At this place, the radar chart becomes handy. We can even plot two or more objects on the same axes with different color webs to compare them by their distribution.
What kind of data you can visualize with it?
When the count categorical data is high, then the radar chart is the best. Assume you want to compare different managers on their skill sets like communication, punctuality, team player, technical knowledge, problem-solving, etc., then the web of every manager will represent the best skill each has.