Under following conditions-
mvwithin the same HDD partition
mvto a different partition in the same HDD
mvto a different device (e.g. USB HDD)
Is the complete file moved or is it a very small change like some pointer reassignment ?
It's up to each filesystem how to handle a move within the filesystem (also known as renaming a file), but filesystems pretty much universally handle it by updating directory entries without moving the inode or file contents.
A move between filesystems (it doesn't matter if it's on the same physical medium or not) is handled as a file copy followed by a delete. This is in fact exactly what the