Traditional photo editing is ‘destructive’. That means every adjustment you make permanently changes the pixels in the photo and there’s no way back unless you’ve saved a copy of the original and you’re willing to start again. ‘Non-destructive’ editing is fully reversible. You can go back and undo or redo all of your editing work […]
A Snapshot is a record of the current image state while you're editing it. You can create a Snapshot in Photoshop or Lightroom when you reach a point that you think you might want to return to during editing. You can save a number of Snapshots to quickly compare different editing steps.