SMPTE timecode stamps every frame with an address, and show systems chase it: when the playback rig runs 01:23:45:12, the video server, lighting desk, and pyro controller all know exactly where the show stands. Distributed as audio (LTC) or over MIDI (MTC), it is how arena productions hit cues in frame accuracy night after night.
Timecode shows trade spontaneity for precision: the set is a timeline, and everything prepared lands perfectly. Hybrid designs are the norm, timecoded spine with improvised layers over it.
Club and improvised sets rarely touch it; tempo-level sync via Ableton Link or audio analysis fits looser performance. The two philosophies define the spectrum visuals rigs live on.