7. A document processing system comprising: a system memory; a processing unit that executes instructions stored on the system memory to create a document processing application configured to merge together at least two documents to generate a third document; a first document configured to be processed by the document processing application, the first document storing content and metadata, the content of the first document including at least one data unit, the metadata of the first document including a unit identifier and an edit identifier associated with each data unit, the unit identifier of each data unit being generated when the data unit is created, the edit identifier of each data unit being generated when a modification to the data unit is saved; a second document configured to be processed by the document processing application, the second document including at least one data unit, wherein the document processing application is configured to: compare the unit identifiers of the first document to unit identifiers of the second document 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; compare 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; insert directly into the third document data units of the first and second document that are associated with non-matching unit identifiers; insert 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 merge into the third document data units of the first and second documents that are associated with matching unit identifiers and non-matching edit identifiers.
7. A document processing system comprising: a system memory; a processing unit that executes instructions stored on the system memory to create a document processing application configured to merge together at least two documents to generate a third document; a first document configured to be processed by the document processing application, the first document storing content and metadata, the content of the first document including at least one data unit, the metadata of the first document including a unit identifier and an edit identifier associated with each data unit, the unit identifier of each data unit being generated when the data unit is created, the edit identifier of each data unit being generated when a modification to the data unit is saved; a second document configured to be processed by the document processing application, the second document including at least one data unit, wherein the document processing application is configured to: compare the unit identifiers of the first document to unit identifiers of the second document 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; compare 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; insert directly into the third document data units of the first and second document that are associated with non-matching unit identifiers; insert 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 merge into the third document data units of the first and second documents that are associated with matching unit identifiers and non-matching edit identifiers. 12. The document processing system of claim 7 , wherein the document is a text document.