X-Author can be used to compare or merge any two versions of an agreement document in Salesforce. X-Author uses Microsoft Word's compare and merge feature to allow you to compare agreements from two different agreement records.

Compare: The comparison is done based on Word's Legal Black lines compare functionality. Compare Legal Black Lines compares the documents and displays only what changed between the two documents. The documents being compared are not changed. This type of comparison is always displayed in a new third document, typically named Compare Result. Microsoft Word displays a new, third document in which tracked changes in the baseline document are accepted and changes in the selected document are shown as tracked changes. The documents being compared are not changed. There are two ways you can compare the agreement documents:

1. You can compare the different versions of an agreement document within the same agreement record, or,
2. You can compare the different versions of an agreement document from two different agreement records.

Merge: Merging documents uses Word's Combine feature to merge selected documents. Merging documents can be advantageous if you have one version of the document that has been redlined, and a regenerated version in the latest format (dynamically inserted fields, new clauses, etc.). Original (pre-merged) documents do not get changed. Merging the documents displays a new third document, named Merge Result. At this point, you can accept and reject any of the redlined elements in the combined document and check-in the document as a new version.