Destructive vs. non-destructive
Destructive editing changes the original file. Non-destructive edits sit on top and can be undone. For podcasting, you almost always want non-destructive — and you always want a backup of the raw recording.
Destructive editing means your cuts and effects are baked into the file itself — the original audio is overwritten. Non-destructive editing means your changes live on top of the file as instructions; the raw recording is untouched, and any cut, effect, or volume change can be undone.