In 2003, Steven Strogatz opened his book Sync with this assertion: "At the heart of the universe is a steady, insistent beat: the sound of cycles in sync."
Along with other authors like William Benzon (Beethoven's Anvil) and Steven Johnson (Emergence) who have sought to explain emergent patterns of collective behavior, Strogatz pushed the term sync to stand for our best understanding of how amazing "feats of synchrony" are accomplished without a conductor or even a playbook.
Sync, as it has evolved over the past decade, is a form of emergent cooperation that occurs when humans mirror each other in rhythmic patterns. Sync has come to stand for the complex principles of synchrony that underlie such diverse human experiences as markets, smart mobs, social networks, and traffic patterns. The mathematics of synchrony claim to foretell the conditions under which such bottom-up cooperation is likely to occur. But in the vernacular, sync means collaboration through shared rhythms, and setting sophisticated rhythms in motion is gradually evolving as a powerful method of seeding collective action.