Selections and masks are subtly different, and the ‘parametric’ masks in non-destructive editors give more flexibility than ever.
Selection Brush
This is a basic kind of masking tools that selects areas of the image as you brush over them. You'll find equivalent tools in most photo editors. In Photoshop, the Selection Brush is a little like the Magic Wand too, finding he boundaries of the areas you brush over.
Local adjustments explained
‘Local adjustments’ is a bit of a catch-all term. It means picking out an area of an image for adjustment while leaving the rest unchanged. So how do local adjustments work and which software does them best?