Editing & Post-Production
Audio sync
Also called: waveform sync, sync clips, syncing footage
Record onto a dedicated recorder or a lavalier and the sound arrives as its own file, attached to nothing. Syncing puts it back where it belongs. Premiere, Resolve, Final Cut and PluralEyes all do it by comparing the camera microphone's rough audio against the good recording and sliding one until the waveforms line up, which is why leaving the camera mic running matters even when you never intend to use it.
Long takes can drift when recorder and camera clocks disagree, so check the sync at the end of a 40-minute take as well as the start.