Definition: Shredded Storage is a feature in SharePoint that splits the Binary Large Objects (BLOB) into smaller pieces/chunks.

When Shredded Storage is enabled, every document including the changes made to the document is stored as chunks in SQL server. When a user updates the file, only the affected chunk gets updated in SQL database instead of saving the entire document every time it is modified.

Some Points:

1. Shredded storage is ON by default
2. BLOBs are NOT shredded when you upgrade from SharePoint 2010 but shreds are generated when you upload or modify a document
3. Shredded Storage feature can be enabled or disabled only on Web Application level. Below PowerShell can be used for the same. Basically we are not turning the feature off but we are increasing the size of single shred to as large as 1 GB. So it automatically eliminates most of the content from shredding in to pieces and will save the entire file.

$WA = GET-SPWEBAPPLICATION HTTP://<>>

$WA.WEBSERVICE.FILEWRITECHUNKSIZE = 1073741824

$WA.WEBSERVICE.UPDATE()

4. Content Save: In SharePoint 2010, if we make any change in the document (even in metadata), a new document is created. With Shredded storage feature in SharePoint 2013, it only stores the changes we have made to the document thus saving lots of storage in the database.
5. Content Read: AS part of the feature, FILEREADCHUNKSIZE property was introduced which is associated with BLOB Cache. BLOB Cache provides HTTP range request support. So when user request for incremental read (incremental read = different version of the same-open file) of any file, only that incremental chunk is retrieved instead of entire file, saving lots of bandwidth over the network.
   NOTE: Incremental read may take lesser time but when you are requesting any file for the first time it may take more time as the document is shredded into pieces and it will take time to collect all those chunks and present to end user.