A Venn diagram is a type of diagram that is used to show all possible logical relations between different sets. It's made up of overlapping circles, which represent the different sets. The first circle in the diagram represents the set of people who are currently alive. The second circle represents people who have died and are now dead. The third circle represents people who were born after you were born and will die before you die (i.e., future generations). The fourth circle represents people who were born before you were born and will live after you die (i.e., past generations).