Layer masking is a non destructive form of isolating an object or color. Para siyang Layer within a layer and it operates on black and white/foreground and background colors. Masking siya na editable on the fly, unlike kapag diretso sa Layer kailangan mo i-undo lahat, kapag naka Layer mask ka ang edit nangyayari sa Channels so mas malambot, mas smooth and mas safe. (parang condom ad).