Important note: editors (and writers) often define these terms differently, so it’s essential to be on the same page—pun sort of intended—before you start the editing process. Make sure you spell out exactly what sort of assistance you’re looking for. Each type of editing demands a different skill set, time commitment, and budget, and you don’t want to be surprised after you get your edits back.
Developmental editing
Developmental editing looks at the “big picture” of a work: structure, organization, tone, theme, promise to the reader (whether or not it has been met), reasoning, and chapter coherence—all of the elements that determine how a reader experiences a book and whether it accomplishes what it set out to do. Developmental editors ensure that the content of a work not only fits but exemplifies the form. As a result, they’re less concerned with the nitty-gritty of fixing grammar and formatting text.
For my developmental edits I provide 1) in-depth comments throughout the manuscript (though no direct edits to the text) and 2) a comprehensive editorial letter assessing the big-picture elements described just above. The letter also includes a brief analysis of individual chapters and an assessment of the book’s title, subtitle, and positioning. The length of the letter varies depending on the manuscript’s word count and state, but in my experience typically runs from six to eight pages.
Line editing
Line editing occupies that hazy, often ill-defined space between developmental editing and copyediting. The term is somewhat controversial (as far as controversy goes in the editing community). Some editors call it “heavy copyediting” or “substantive editing,” while others don’t acknowledge its existence, arguing that developmental editing or copyediting are descriptive enough. As I define it, line editing consists of revising text to provide greater clarity; ensure formal and thematic alignment with a paragraph or chapter; and make it more coherent, professional, and true to the author’s voice. It involves flagging non-sequiturs, gaps in logic, sentences that are off-tone, awkward, or out of sync with the rest of the book—and, where appropriate, revising them directly in the text via Track Changes. It’s developmental editing without concern for structure, copyediting without concern for consistency. It’s playing around in the muck. It’s revising for rhythm and flow. It’s the polish that makes a work more readable, clear, and engaging.
Copyediting
Copy editors review—and, when necessary, correct—the mechanical aspects of a work: grammar, syntax, usage, capitalization, formatting, labels, citations, consistency, etc. (For example, copy editors know that while the noun “copy editor” is generally styled as two words, with no hyphen, the verb “copyedit” is styled closed.) They also do light fact-checking, such as confirming the spelling of names and locations. If only it were that simple, though! Depending on where a work will be published, what constitutes “proper” capitalization or spelling may differ considerably. Conventions vary among the Associated Press, the University of Chicago Press (which publishes The Chicago Manual of Style), and the Modern Language Association, to name just a few of the major style enforcers. Also, many publications and businesses have their own quirky editorial preferences, called a house style. Whatever the style guidelines, the copy editor’s task is to ensure the rules are adhered to. (They also know it’s totally fine to end a sentence with a preposition, and that the passive voice is okay, too.)
Proofreading
Proofreading is the most basic level of editorial prophylaxis. It involves pointing out typos, mismatched formatting, and other superficial goofs that weren’t caught in the copyedit (and there are always some). Proofreaders don’t touch content; they are simply a backstop that makes sure glaring errors don’t make it into publication. Proofreading is usually the last process before publication.
For more information about the different types of editing, and tips on hiring the right editor, check out the free Editorial Freelancers Association e-book Hiring an Editor: A Guide for New Authors. Or just get in touch.