Editorial feedback is the process by which an editor assesses a manuscript, identifies strengths and weaknesses and make suggestions on how the text could be improved.
Those suggestions could address almost anything from plot and pacing through character and point of view to the (crucial) minutiae of prose style. A good editor doesn't apply any sort of template to your work: he or she will just respond honestly and constructively to the text in front of them.
Note that feedback means what it sounds like: editors don't normally make hands-on corrections to your work themselves. It's your book: we only offer advice. View sample editorial reports.