If you are using Photoshop, you should already have encountered the issue of banding in gradients.
This usually happen in 8-bit but, even when working with 16-bit, this can occur if you need to apply an 8-bit filter.
No More Banding is a Photoshop action which automatically converts your document into 16-bit and applies a new layer to the top of your group/document which fixes fixing all the banding.
P.S. There is a detailed read on the technique here.