Defrag

[funf]

Can someone tell me how data is maipulated, file or cluster ?

In other word is the remainder of the cluster eyond the end of a file preserved ?

 

[Chopper]

I'm not sure I understand your question, but if I do:

Only one file can occupy a cluster. One file can occupy more than one cluster, but no more than one file can occupy any given cluster. When a file is manipulated via defrag, copy, etc, the file data is moved - any unused space beyond the end of the file in the last cluster is undefined and you can make no assumption that the undefined contents are copied to the new location.

So, the one-word answer: file.