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 […]
This is where you don't make any direct changes to the pixels in a photo, but save processing instructions alongside it. These instructions are used to change the appearance of the photo when it’s displayed and edited but are not applied permanently unless you export a new, 'processed' image. Photoshop started the idea of non-destructive editing with its adjustment layers, but other programs have now implemented it fully, so that Lightroom, Capture One, ON1 Photo RAW and a number of other photo-editing tools are now fully non-destructive.