Question

.. What do you call a non-fictional motion-picture intended to “document reality,
primarily for the purposes of instruction, education, or maintaining a historical
record"?​

Answer 1

it can be called as a documentary

Answer 2

Such a non-fictional motion-picture is called a documentary.

A documentary, as the name suggests, is like documents, but in a movie format. Since documents deal only with facts and do not contain imaginative inputs, documentaries too are factual. They present the truth as it is, without adding any fictionalised bits to it.

Documentaries are educational in nature. They seek to teach and spread awareness about the topics they cover. For instance, a documentary on whales tells us little known facts about the species. Similarly, a documentary on tea tells us about how the very first tea plantations were set up in India and how it is now. A documentary on the traditional embroidery of Punjab, called 'phulkari' tells us about how the art came into existence.