John Venn: English Mathematician
John Venn (August 4, 1834 - April 4, 1923) was an English mathematician/logician who invented the Venn diagram.
His diagram clearly shows the similarities and differences for two different sets; it is a visual way to represent sets, and their unions and intersections. Venn's diagrams were first published in 1880, in "Philosophical Magazine and Journal of Science" - Venn's article was called, "On the Diagrammatic and Mechanical Representation of Propositions and Reasonings."
A simple Venn diagram pictures two circles (sets) with an overlapping subset (things that the sets have in common). The diagram divides the sets into four distinct regions, elements (things) that are only in the set A, elements that are only in the set B, the intersection (things that are in both set A and set B), and elements that are in neither set A nor Set B.
