Last Friday was our first furlough day. That means our next paycheck will be for nine days rather than ten. I put my three day weekend to good use prepping Glyn's galley.
In the industry there are galleys, ARC (pronounced 'ark'), and proofs. Some people use the terms [nearly] interchangeably. There are distinct differences in the three. You can google them for more information (which varies from source to source), but in a nut shell they mean:
Galley is a rough out of the coming book. It is gross (as in rough) formatted. There is no cover art. Only a handful of galleys are printed. One for the author, of course. A couple for advance reviews. It likely has not been fully edited and certainly not line edited (proof read).
Most people in the industry who do book reviews understand that this is about the storyline, not about the polishing yet to come. Amateur reviewers will comment on grammar or typos. Professionals don't. They know galleys aren't the finished book.
ARCs are advance reading copies. They are generally nearly the done deal and are often the final book. They have cover art. Some printers print 500 of these give away books for their better known authors. They are strategically given to key people with the understanding they are to promote this book. As you might guess, Cactus Rain Publishing does not print ARCs. They simply aren't in the budget.
Proofs or proof copy or proof books are just that - the final version of the book. It is the last chance to see the book before the print run. Very few corrections or changes are made at this point. Those should have been caught by now.