I never thought about it, but it makes sense there are different editing processes for each phase of story development.
A Developmental Editor works with the author on developing the story. They will check the structure and content of your book. You may or may not need this service, depending on your skill level. For a detailed article on how to work with a developmental editor, check Jane Friedman’s website.
A Line Editor looks at the author’s creative content, writing style and language, making sure the use of language is clear and readable. A line editor will point out overused/unneeded words and sentences, where dialogue needs to be tightened, and confusing scenes, just to name a few.
A Copy Editor gets down to the nitty-gritty of finding spelling, grammar, and punctuation errors. The copy editor will look for consistency in your use of words and statements. You can’t have someone with blue eyes in the beginning of the story and brown eyes at the end – unless, of course, contact lenses are part of the story!
Thanks to the New YorkBook Editors website for pointing out the differences between line editing and copy editing.