Origin: The idea was first proposed in 1929 by Hungarian author Frigyes Karinthy in a short story collection.
Popularization: It gained wide attention after a 1967 experiment by psychologist Stanley Milgram, who conducted a study using letters passed from person to person to reach a target individual.
Modern fame: The idea became a pop culture meme in the 1990s thanks to the game "Six Degrees of Kevin Bacon," which challenged people to connect any actor to Kevin Bacon through mutual film roles in six steps or fewer.
Online Networks Proved It
Facebook (2011 study): Researchers found that the average degree of separation between any two Facebook users was 4.74 (later updated to 3.57 in a 2016 study). That’s even fewer than six!
Microsoft (2008): Analyzed 30 billion instant messages and found the average chain between any two people was 6.6 steps—very close to the original theory.
Social Media Supercharged It
Facebook, LinkedIn, and Twitter created digital maps of connections, making it possible to trace how you're connected to virtually anyone—celebrities, politicians, or strangers across the globe.LinkedIn in particular gamified this with its “1st, 2nd, 3rd-degree connections” system.