1. A method of merging a first document with at least a second document to generate a third document, each of the first and second documents including one or more data units, each data unit being associated with a unit identifier and an edit identifier, the method comprising: obtaining the unit identifiers of the data units of the first document; obtaining the unit identifiers of the data units of the second document; comparing the unit identifiers of each of the first and second documents to the unit identifiers of the other of the first and second documents to determine whether each of the unit identifiers is a matching unit identifier or a non-matching unit identifier, wherein each of the matching unit identifiers indicates corresponding data units of the first and second documents, and wherein each of the non-matching unit identifiers indicates a data unit of one of the first and second documents that does not correspond with any data unit of the other of the first and second documents; comparing edit identifiers of the data units associated with the matching unit identifiers to ascertain matching edit identifiers, each of the matching edit identifiers indicating the data unit of one of the first and second documents matches the corresponding data unit of the other of the first and second documents; inserting directly into the third document data units of the first and second documents that are associated with non-matching unit identifiers; inserting directly into the third document data units of the first and second documents that are associated with matching unit identifiers and matching edit identifiers; and merging into the third document data units of the first and second documents that are associated with matching unit identifiers and non-matching edit identifiers.