Performance is ‘restored behaviour’: rehearsed, repeatable action found in ritual, play, sport and everyday life as well as theatre.
The longer story
Schechner expanded 'performance' far beyond theatre to include ritual, play, and everyday life—anything that's 'restored behaviour,' twice-behaved, rehearsed. Performance studies emerged as a field that crosses boundaries. His continuum from ritual to theatre to entertainment helps analyse different modes of performance and their social functions. For research on live events, Schechner provides foundational concepts: what kind of performance is this? What does it accomplish? How is it framed?