What they are
Before a book is published, the publisher produces pre-publication copies: galley proofs (long sheets for proofreading), uncorrected proofs and advance reading copies (ARCs) (bound, often in plain printed wrappers, sent to reviewers and booksellers). They are printed in small numbers and precede the published first edition.
How to identify them
Look for plain printed wrappers (not a dust jacket), and statements such as “Uncorrected Proof,” “Advance Reading Copy,” “Not for Sale,” or a tentative price/publication date on the cover. Text may differ from the published book. They have no number line because they precede the trade printing.
Are they first editions?
In the strict trade sense, the published first edition is “the first edition.” But proofs and ARCs precede it, exist in tiny numbers, and are highly collectible for important books — sometimes more so than the trade first. They are described as proofs/ARCs, not as the first edition.
Frequently asked questions
Is an advance reading copy a first edition?
It precedes the first edition and is collectible, but it is described as an ARC or proof, not as the trade first edition. For some landmark books the proof is the most sought-after form.
How can I tell a proof from the real book?
Proofs and ARCs come in plain printed wrappers (no dust jacket) and usually say 'Uncorrected Proof' or 'Advance Reading Copy — Not for Sale.' The text may differ from the final book.