Qualifier
A qualifier isolates part of your image based on color, so you can adjust only that area. You pick out a specific skin tone or a blue sky and leave the rest alone. It's the engine behind many secondary corrections.
In DaVinci Resolve you click the color you want to select with the qualifier, then refine the selection with sliders for hue, saturation and brightness. You often combine it with a power window to limit the selection to one area. A clean selection is worth gold, because messy edges stand out instantly. Tip: use the highlight view to see exactly what you're selecting, and denoise your image first for a cleaner qualifier.
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The presets on this site set these adjustments up for you as a starting point, which you then fine-tune to taste.