ELI5: Explain Like I'm 5

Venn diagram

A Venn diagram is a way of showing how two or more things are related. It's kind of like a picture - each circle in the diagram represents something, and the overlapping parts show where the two things overlap. For example, if you want to compare cats and dogs, you might put cats in one circle and dogs in another. The overlapping parts of the circles would show what cats and dogs have in common.