Find the differences between two documents

In Side by Side, Compare reads both documents and lists every difference, marked on the pages of both halves.

Steps

Open Side by Side with the two documents (Review › Compare…). See "Compare two documents side by side".
Choose Compare. While it works, the bar shows how far it has got; choose Stop to stop.
The Differences list opens with a short note on what is compared, then shows each change with the pages it is on, left and right.
Choose a change to take both halves to it. Its marks are drawn stronger than the others. For a page only one document has, the other half goes to the place the page would be.

Text changed: the words that differ, each word marked on its own where each document has it, so a word kept between two changes stays unmarked.
Moved: text that is the same but sits somewhere else on the page.
Page size changed: a page that is bigger or smaller in one document.
Annotation added, Annotation removed and Annotation changed: comments and marks, including a changed note or colour.
Picture changed: images and drawings that differ, where no text change explains them.
Page added and Page removed: pages only one document has. The pages after them are still matched to their counterparts, so one added page does not make every later page look different.

Pages are matched by what is on them, not by their number. Scanned pages with no text are matched by how they look.
If no page matches, the list says so: These documents have no pages in common. They look like different documents. Every page is then listed as added or removed, which is true, and not a fault in either file.
A word is marked by its share of its line, so in some fonts a mark can sit slightly off the word.
Very small changes to pictures can be missed.
Up to 1,000 differences are listed.
If a document changes while it is being compared, choose Compare again.

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