To have the right to delete a Story you have to meet one of the following conditions:
be the author of this Story
have the right of "contributor" to the space or more
have the right of system "coordinator" or more
Deletion consists of irreversibly wiping out Stories on the platform. It also disappears from any Stories pointing to them.
To delete content you can work:
individually on every content
on a selection of content by using bulk actions