Google Doodle Says Happy Birthday To John Venn, Creator Of The Venn Diagram. The man who invented the elegant overlapping circle diagrams would have been 180 today.

Use Venn diagrams to illustrate data in a logical way which will enable you to see groupings and sets clearly. ... If we now look at the Band Y circle, we have all the sections complete except one.

An Italian architectural historian thinks Giacomo Andrea de Ferrera, a Renaissance architect and da Vinci friend, drew the man-in-circle diagram first Leonardo da Vinci's drawing of a male figure ...