Small-world network

A small-world network is a type of graph in which most nodes are not directly connected to one another but can be reached from every other node through a small number of connections. This concept was popularized by psychologist Stanley Milgram in the 1960s through his "six degrees of separation" experiment, which suggested that any two people in the world could be connected through a chain of acquaintances involving, on average, just six intermediaries.