What: Treating colour (temperature, saturation, curve) with an intent that serves the image's mood.
Why: Intentional grading builds a signature and mood; random grading ruins the image's honesty.
How: Define the state first (warm nostalgia, cold solitude), then adjust temperature and saturation to serve it moderately.
Common mistake: Maxing out saturation so the image looks artificial.
Exercise: Grade one photo in two different moods (warm then cool), and compare their emotional effect.