The lightest and fastest form of editing; it is also the last stage of editing before print or online publication, and focuses on ensuring proper punctuation, grammar and spelling.

Proofreading will fix typos and grammatical mistakes, as well as immediate consistency problems or obvious typesetting issues, but it does not focus on deeper structural review of the provided copy. Therefore it's important to use proofreading only when the final copy has been approved, and all that remains is to make sure no simple errors and mistakes creep in. If the text is edited again after it's been proofread, the prior proofreading will be wasted, as the entire copy will need to be re-checked after any substantial changes are made.

A step up from proofreading, copy editing provides a more in-depth level of mechanical editing. Copy editing will catch things like missing sentences, phrasing that could be touched up, frequent reuse of words and phrases, etc. A copy-edited text will be given a consistent, polished style, in addition to being given the same treatment as during proofreading.

As copy editing is a mechanical editing stage, it does not allow for deep structural work on the text. Whilst issues such as ambiguities or clear factual errors will be flagged, and structural issues in the story such as characterisation or plotline will be flagged and reported, it is not the editor's call how to fix them, nor is there enough time for fact-checking or rewriting of every passage. The right time for a copy editing pass is generally when the author feels the text is done, the prose is solid and flows well, and no more than minor revisions are anticipated. A successfully edited copy will normally progress to typesetting and a final round of proofreading.

See also an example of a copy edit.

Line editing is usually considered to be the level where substantive—rather than mechanical—editing work starts. At this stage, particular attention is given to the language used and how it fits the tone intended, whether the text is readable and precise, and to fixing any stylistic issues and tweaking the pacing.

Since line editing asks for a substantive review of each and every line, the editor is given a significant degree of latitude when it comes to working with the text. This will include rewording or rewriting awkward passages, tightening up sentences, and even removing or reordering text in order to improve pacing and flow. Inconsistencies in plot or confusing dialogue will be fixed where possible, or communicated back if the degree of rework necessary is deemed too great. Overall editor feedback will also be given.

Since line editing might change the text considerably, or require actionable feedback, it is a good idea to allow good time for another revision and any questions from the editor. Although the language of the copy might change substantially, the contents will stay broadly the same, and the editor will not change things such as plot points or characterisation beyond what is required to ensure consistency.

See also an example of a line edit.

Developmental editing is the deepest and most substantial level of editing, and has the editor getting involved in the fundamental structure of the text. Major decisions, such as adding, dropping or changing plot elements, changes to characters, or changing the way technical information is laid out might be made here. Drastic changes might be suggested to the outline or even the setting of the story, in order to improve it.

At this level the editor works very closely with the author, and takes an active coaching role, suggesting any changes they believe will help the text serve its intended role. A developmental edit might be requested in order to fix a draft that doesn't work, or the editor might get involved before a full draft is even written and help the author shape the text on the way to the first manuscript.

Although the editor will work with the author and coach them, they will not normally write the text, other than as an illustrative example to convey the idea of feedback being given. If more help implementing the suggestions is needed, it is no longer editing work, and becomes a writing service instead.

Also, since the text will be undergoing significant structural changes, it will essentially revert to first draft in terms of readiness for publication, and will require a full editorial treatment before it can be published.

In many ways the little brother of developmental editing, an evaluation takes a look at the manuscript and assesses it from several perspectives, in order to produce a so-called editorial letter. The letter is typically several pages long, and will go over multiple aspects of the draft received, such as:

• Pacing
• Characterisation
• Story clarity and consistency
• Content presentation in non-fiction writing
• Mechanics of the language used (i.e. grammatical issues or stylistic choices)

The editor will detail the parts they think are strong, and those they feel could use improvement. The letter thus serves as a tool for the author to get a professional high-level opinion on how well the text is progressing.

While getting a developmental editor is like hiring a personal coach, an evaluation is more akin to getting a physical done by a doctor. The editor will identify strengths and weaknesses, and give suggestions on how they feel the work can be improved, but they will not directly participate in that process. This makes an evaluation much less involved and much quicker, and the service much less expensive than a full developmental edit.

Authors will frequently request an evaluation of their manuscript prior to sending a query letter to potential publishers. It is also useful as a checkpoint for authors, if they're not sure whether their draft is on track. And if turns out that it's not, it might well make sense to choose developmental editing assistance then.

It's also possible to request a partial evaluation of a portion of the manuscript. This will identify many of the same issues a full assessment would (albeit without the ability to catch plot holes and other problems affecting the work as a whole), but can be significantly less demanding in terms of time and money required. Though keep in mind that a proper assessment requires a lot of thorough attention and is never quick.

Please note that my evaluations do not include any assesment of marketability, business potential, or fitness for publication. I am not a publisher and can't make any claims about an inherently variable and highly subjective matter such as whether there will be a publisher or an audience for a book.

See also an example of an editorial letter.