A Venn diagram is a graphic representation of the relationship between two or more objects or groups of objects. The relationships are represented by circles. They show how distinct sets are related mathematically or logically. The shared elements are represented by overlapping circles, while the separate elements are represented by non-overlapping circles. The relationships are depicted in this visual graphic using unique Venn diagram symbols. Many operations can be done on given sets in set theory. Venn diagram symbols can be used to symbolize these operations. Venn diagrams are useful for visually illustrating set theory processes. The most important Venn diagram symbols are listed, though there are roughly 30 total.