This document discusses different types of documentaries and how the genre has evolved. It defines documentaries as consisting of official documents or using real events and interviews to provide factual reports. There are six main documentary styles: observational, expository, participatory, reflexive, poetic, and performative. Modern documentaries have become more interactive, abstract in filming style, and hybridized. They appeal to wider audiences through techniques like non-diegetic sound and reenactments. Examples highlighted include experimental silent films from the 1920s and more recent films that expose controversial truths in unflinching ways.