4. Proofreaders do the final editing, and they're a special kind of editor. They see the missing comma or the left-out words. If you typed was for saw, a good proofreader jumps on it.
He is the person who catches the little things that we tend to overlook. You may read a track change that says, "You used begin three times in this paragraph," and he suggests how you can rewrite to get rid of one of them and perhaps two.
They see the manuscript after the design is completed, and the photos, captions, front matter, and back matter are all in place. They check headings, page numbers, typeface styles, and make sure that corrections by you and the the copyeditor have been inserted.