Why drupal need hidden option in comment settings of content types? In content type setting in drupal, we have tab comment setting .The comment setting on future content of this type will default to:


Hidden: No comments are allowed, and past comments are hidden.
Closed: No comments are allowed, but any past comments remain visible.
Open: Any future content of this type is open to new comments.


Why do we need HIDDEN option? It  does not make sense in content type setting . If we set this option - in any new nodes that will be created next  - comment will be closed.

This option has sense only in particular material, if it has comments.

Please explain me why this option need in content type settings? 

Thanks...
This option has sense only in particular material, if it has comments.


Precisely. So you should use this option when a content type has comments that you don't want to delete, but don't want to allow people to see either permanently or temporarily.

If you don't need that option, you don't need to use it. But its existence makes perfect sense.