Weak ties are “casual acquaintances—friends of friends—people who are neither strangers nor close pals.” They represent “the links that connect people who have acquaintances in common, who share membership in social networks, but aren’t directly connected by the strong ties of friendship themselves.” These are the people you know of, not the people you know
Weak ties can be extremely powerful, even more so than strong ties
In network science, weak ties function as Network Shortcuts—connections that bridge distant parts of the social network and make the world “small.”