Documentary film

some definitions:

Strictly speaking, documentary films are non-fictional, factual works of art. Originally, the earliest documentaries were either short newsreels, instructional pictures, or travelogues (termed actualities) without any creative story-telling or staging. But they have branched out and taken many forms, and have sometimes become propagandistic and non-objective. Mockumentaries are comedic parodies of documentaries. Some documentaries have been considered propagandistic. --(filmsite.org)

A production is considered a documentary if it takes as its subject actual people, places, and events and presents them in a non-fictional context. --(Chicago International Children's Film Festival)

Wikipedia has a full article, and a list of movie genres which includes propaganda film