What Is a Venn Diagram?

Learning How to Compare and Contrast Two or More Things

Example of a Venn Diagram
A venn diagram is used to compare and contrast two or more things. In this example the green pegs represent the things the blue and yellow pegs have in common. Credit: AntiMartina/E+/Getty Images

A Venn diagram is a visual tool used to compare and contrast two or more objects, events, people or concepts. It is often used in language arts and math classes to organize differences and similarities.

This simple graphic makes it easy for students to understand how two things are both different and alike at the same time. 

What is a Venn Diagram?

Venn diagrams can become complicated, but in its simplest form, it is two circles that overlap in the middle.

Using the photograph at the top of this page here is how a Venn diagram works:

  • Each circle represents one item that is being compared: Item 1 and Item 2.
  • The yellow pegs represent the qualities that are unique to Item 1. The blue pegs represent qualities that are unique to Item 2.
  • The green pegs represent qualities that both Item 1 and Item 2 have in common.

Simple Venn diagrams can be used to compare more than two things as well.

How is a Venn Diagram Used?

Children will often learn to use Venn diagrams in language arts. It can be used to compare characteristics in two different books or two characters in the same book.

A Venn diagram can also be used to:

  • Visualize information for a compare and contrast essay. For example, a student may need to compare the differences between a fish and a whale. They are alike because they both live in the water and that is written in the overlap. Only fish have scales so that would go in the fish-only circle. Only whales breath air and that would go in the whale-only circle.
  • Brainstorm ideas when writing a story. For example, each circle may represent a character in the story and a student may write down personality traits or events that happen to each character separately, then use the overlap to figure out where the characters' interact in the story.
  • Help make decisions. A Venn diagram can also be used like a list of pros and cons when making a decision. Maybe your child wants to get a pet and you have given permission, but they cannot decide whether they want a dog or cat. You can use a Venn diagram to help them decide (and get a teaching moment in at the same time).

    More Venn Diagram Examples

    Compare Jobs in the Government

    A student may need to compare the executive and legislative branches of the U.S. government for social studies. In one circle they would list the responsibilities and powers of the President and in the other circle the job details of the Congress.

    In the center would be commonalities like the fact that they are both elected to office or have term limits.

    Compare Dr. Seuss Books

    A Venn diagram can be used to compare two books by the same author and Dr. Seuss is a popular topic for young children.

    When comparing "The Cat in the Hat" and "Green Eggs and Ham" we can see that:

    • Both Books: Rhyme. Include hats and fish. Both characters are asked to leave, get upset and think they don't like something.
    • "The Cat in the Hat" is unique: There is a cat and six characters, stays in the house and includes people.
    • "Green Eggs and Ham" is unique: There is no cat and only two characters, the story moves to different locations and includes no people. It does have green eggs and ham!

      Different Ways to Make a Venn Diagram

      Venn diagrams use two or more circles and there are a few different ways to make them. They can be interactive and fun and here are a few ways to make a Venn diagram

      • Draw the circles on a blank piece of paper and fill in the information. Use water color paints or crayons to color in the finished diagram.
      • Use a dry erase board and three different colors of marker.
      • Place two hula hoops on the floor and cut out strips of paper to write on and place in the correct circle. Pieces of string laid out in a circle can be used as well.
      • Include pictures cut out from magazines or newspapers to illustrate the differences and similarities.

      Continue Reading