Every Document in SharePoint 2013 is now stored as multiple “shredded BLOBS” in the new “DocStreams” data table.Whenever a new Version of a document is created, a new Record is written in this data table that contains only the “Shred BLOB” of the original document that corresponds to the Change, merged with the new Changes.In other words a new Blob with Changes is added as a new row in the table.Each BLOB that gets added Contains a numerical Id that represents the source BLOB.At the end it is the job of BLOB Index to keep the track of Blobs and to create a full file with the Combination of entries that point to the unchanged shreds of the previous version(s) and the entries that point to the newly added Changed shreds.