Color balance. The second one has corrected color.

In a darkroom, when printing color prints, you usually have to change the color pack(color balance) because an image will have a blue cast, or a yellow cast, or a red cast, or whatever. You balance the colors so that the image is more neutral, this is what the "ROC" option does for you.

Yes, some people like a color cast, and depending on the image, it can be what one wants, but, it's "technically incorrect."

Hope this helps.