A Venn Diagram shows the logical relationships between groups of things. They are most often shown as two circles that intersect in the middle of the page. Attributes that are exclusive to each group are listed in the circles, and attributes that are shared by both groups are listed in the intersecting space. The diagrams can be used in the classroom as a tool to help students compare and contrast two objects or concepts. The Venn diagram can also be used in teaching mathematics. For example, one circle can represent numbers which are multiples of two, and the other multiples of three. Students can then start counting from 2 and add numbers to the relevant sections of the diagram in order to visualize how the multiples are related.