Six degrees of separation!
This meme and the play, movies, and games it generated did more to introduce elements of network theory to the general public than years of public education. Movie buffs play the Kevin Bacon Game, trying to link two actors through movies in which they appeared with Kevin Bacon. Mathematicians proudly announce their Erdös number (when they have one), the number of co-written papers away they stand from a paper co-written with the famous Paul Erdös.1 Throughout this chapter networks play an essential role in visualizing ...
