TL;DR

Derek Muller dives into the “six degrees of separation” idea by simulating Watts-Strogatz small-world networks: how random shortcuts and “weak ties” make our social graph surprisingly tight, and why diseases (or memes) can zippety-zap around the world in no time.

Along the way we meet network hubs born from preferential attachment, explore how simple Prisoner’s Dilemma decisions shape connectivity, and see that your own choices—who you link with and how—can actually warp the world’s network for better or worse.

Watch on YouTube