When I worked as a disc jockey, recording engineer, and interviewer back in the 70s and 80s, all we had at to record and edit with was analog tape.
Editing the analog tape was a one time destructive process involving a yellow crayon, white sticky tape, and a razor blade. The point at which one wanted to make an edit, like removing a throat clearing, or an "uh", or moving one section of music from one place to another, meant you carefully marked where to cut (at a 45˚ angle) both sections of the tape with your razor blade, then "glue" it back together with white tape. The offending piece of tape you didn't want made its way to the editing room's floor, to be swept up with the garbage.
Once digital editing stations arrived all that changed.
Modern editors are non-destructive. They use what is called an EDL (Edits Detail List), that documents all the cuts, moving of data, additions of filters and equalizers, gain changes, etc., etc.
They are just play acting. No actual changes are ever being made to the original files.
When we edit on the Pyramix system at Octave Studios, for example, the original master files of DSD256 are never touched. Instead, the editor "synthesizes" the changes in real time as if it were actually happening. You do whatever you wish and the system merely remembers your every move (which is why you can undo anything you did).
Once you're happy, you render the file and the computer sets to work generating an entirely new file copied from the master but now with all the changes you asked for.
The beauty of this splicing and dicing method is that the original master files are never touched.
Oh how we would have been happy to have something like this back "when".
Progress!
