Comparing documents is helpful for those who want to see what the subtle differences are between what appears to be two similar documents. Combining documents helps those who also have similar documents, but want to combine the two without having to manually go through each document to copy and paste in the differences between the two. Either way you can decide whether or not you want to compare or combine documents into a separate document so as not to disturb the originals. I first create a new blank document, then on Review Tab, in Compare group click Compare button to Combine or Compare and then add the two documents to compare.

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