What it is:
A Venn diagram is an illustration of common characteristics.
How it works/Example:
Named after John Venn, a Venn diagram is often little more than two or more overlapping circles (you can use other shapes, too). The places where the circles overlap indicate where items have something in common.
For example, let's say you want to compare the players in the mobile phone industry as The Atlantic did in a piece by Alexis Madrigal:
Why it matters:
Venn diagrams can simplify and summarize analyses considerably. They help cut through the clutter and show the essence of a comparison or argument.