How to find what changed between two versions of a document

The example is a short notice about library hours, before and after an edit. The tool finds 2 changes: 2 lines removed, 3 added. Two sentences were edited and one new sentence was added. Inside the edited lines, the marks land on the opening time and the borrowing limit, the two facts that changed. The sentence about late fees stayed the same, so it shows as plain context.

A text diff works in lines, and the document's line breaks decide what a line is. Text copied from a word processor usually keeps each paragraph on one line, which is what you want. Text copied from a PDF or an email often breaks every few words, at the edge of the page. If the two copies wrap in different places, nearly every line looks changed even when the words are the same.

To fix that, join each paragraph back into one line before you compare. Most editors can replace single line breaks with spaces. Then the diff compares paragraph against paragraph and the word marks show the real edits.

Formatting doesn't come along when you paste plain text. Bold, fonts, comments and tracked changes all drop out, so the diff only sees words. To review formatting too, use Compare on the Review tab in Microsoft Word or Tools, Compare documents in Google Docs.