[Tushar Mehta]

Metadata editing in Calibre does not change the metadata at file level.
It seems that the editing remains at level of Calibre library level.
This means:
After editing the metadata in Calibre, if the epub file is copied at some other place and re loaded in Calibre, the file turns out to be devoid of any edited changes in metadata.

This characteristic is not mentioned anywhere in documentation.

It would be highly desirable if the edited data remains permanently remains embedded in file or Calibre gives option for either way.

- Tushar Mehta.