Definition:Euler Diagram

Definition
An Euler diagram is a graphical technique for illustrating the relationships between sets.

It differs from a Venn diagram in that whereas the latter illustrates all possible intersections between a number of general sets, an Euler diagram depicts only those which are relevant for the situation being depicted.

The following diagram is an example which shows the subset relation $$T \subset S$$:


 * EulerDiagram2Subset.png

The shape of the areas is irrelevant, but usually circles are used.