Photoshop's Hue/Saturation command is growing somewhat long in the tooth. For example, if your primary purpose is to increase the saturation of an image, you're better off exploiting the Vibrance command or the Lab mode.

And yet, Hue/Saturation does something that no other feature can do: It lets you edit one range of colors independently of all others -- without defining a selection or mask -- all from inside a single dialog box or palette. And it does this so very easily and so very credibly, that you can get in and out of an image without anyone being the wiser.