# Category:Venn diagrams

- These are comics that relate to Venn diagrams.
- They should not be confused with Euler diagrams although some of the comic that mention Venn diagrams actually shows Euler diagrams instead.
- If Venn diagrams are mentioned, even though it is an Euler diagram, not a Venn diagram, then they will still be included here.

- Randall seems to have made mistakes, or maybe done this on purpose as indicated with the comic 2721: Euler Diagrams.
- Apart from that comic where he mentions that he wishes to call all Euler diagrams for Venn diagrams he has also made the "mistake" two time before:
- 1180: Virus Venn Diagram
- 2090: Feathered Dinosaur Venn Diagram
- All three are now included in both categories, as Venn diagrams are mentioned even though they are not drawn!

- A Venn diagram shows all possible combinations of two or more sets, including those with no elements, and therefore all of the circles must intersect.
- An Euler diagram need only depict the non-empty combinations, and therefore does not have this constraint.
- All Venn diagrams are also Euler diagrams, but not the other way around!
- Thus this category is a sub category of Euler diagrams.
- Only the three mistake comics should be included directly in both categories.

- Apart from that comic where he mentions that he wishes to call all Euler diagrams for Venn diagrams he has also made the "mistake" two time before:
- In a Venn diagram every possible intersection must be shown.
- In general for an n component Venn diagram there are 2
^{n}hypothetically possible zones, corresponding to some combination of inclusion or exclusion in each of the component sets. - A Venn diagram with 2 circles, see 668: Pandora, has 2
^{2}= 4 zones; one overlap zone, two zones without overlap and one outside zone. - 2122: Size Venn Diagram is the first comic to include five components, previously only Venn diagrams with two or three circles have been used in xkcd. It thus has 2
^{5}= 32 zones.

- In general for an n component Venn diagram there are 2

## Pages in category "Venn diagrams"

The following 12 pages are in this category, out of 12 total.