2. Closed
Open
An closed documentary is a documentary that leaves nothing left
to be said about the topic, the exposition is stated.
An open documentary is a documentary that leaves unanswered
questions and leaves more to be said
3. Single
stranded
Multi-stranded
A single stranded documentary only covers one topic but includes
different areas around the topic
A multi-stranded documentary covers multiple topics, covering
different areas of each.