Difference between two lists
The set operations on their own, when that is all you need: A minus B, B minus A, the items common to both, and the union. Copy any one of them on its own, which is what you want when a spreadsheet already does the rest.
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What the four results mean
A − B
Everything in list A that is not in list B. Use it to find books in your master list that are missing from a second list.
B − A
Everything in list B that is not in list A — the mirror image, which is usually the new items you were looking for.
A ∩ B (intersection)
The items the two lists share. With “Ignore case” on, a capitalisation difference does not hide a match.
A ∪ B (union)
Everything from both lists, with duplicates removed — the combined list if you wanted one.