Seeing these terms questioned and bandied about (sometimes confusingly), I thought I'd put up what I've come to understand the general publishing industry understanding is. The idea being that if we use terms more consistently, it may promote understanding.


Beta Reading

Once an author has pulled together the whole of their effort, or a major portion thereof, other eyes are helpful in polishing the effort before it's presented to publishing professionals (or as a first step in self-publishing).

Thus a beta reader is a non-professional reader that goes through a manuscript with an eye towards how they believe the story might be improved and presented. Such entails concentrating on characterization, setting, believability, flow and pacing, continuity, and plot holes (missing, contradicting, or illogical aspects). It is not necessarily very detailed critiquing, but such may be done on a portion of the effort so the author has an idea of how they might rewrite if they see fit.

Beta readers are not explicitly editors, and certainly not proofreaders, but can serve the editing context to the extent of their abilities. In this aspect issues with grammar, spelling, and formatting may be noted for readability, and the beta reader might even assist with fact-checking if applicable.

At this stage, the more readers that offer suggestions on how to improve an effort, the better the author might prepare for publishing. This is the function of the beta reading collective here, as Writing Forums (dot com) is not intended to function as a professional publishing house.


Editing

Editing is the publishing industry process of selecting and preparing works to be published. Selecting and acquiring a work for a publishing house is the role of Acquisitions Editors. Other Editor functions might be organizing anthologies and other compilations, producing definitive editions of a classic author's works (scholarly editor), and organizing and managing contributions to a multi-author book (symposium editor or volume editor).

The aspect of the elastic term editing that may strike fear in an author's heart is more specifically Copy Editors. Their function is correcting spelling and grammar, and on the whole aligning the presentation with house styles. This function is nowadays often outsourced to freelance copy editors the publishing house has trusted relationships with.


Proofreading

Proofreading is the final step (or cycle) in publishing, and as such is essentially verifying a production proof reflects the final edited effort. That is, the sole responsibility of a proofreader (or team thereof) is to ferret out errors in replicating a work for public consumption.