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An user can view all components of story without any procedure.
Logging in to an account enables more actions:
Any logged in user can write a comment to a story.
If an account has a contributor permission for a story, the user may contribute to the content of the story. A story will have one or more contributors.
If an account has a moderator permission for a story, the user can change various attributes of the story and also edit contents of the story. A story may have one or more moderators.
Attributes include: title, genre, summary, fandom (can be Original Fic), etc.