This document discusses different types of documentary films: 1) Docusoaps are long-running documentary series that follow individuals or groups, like Big Fat Gypsy Weddings, and were popular in the 1990s. 2) Reality TV progressed in the late 20th century and provides both entertainment and useful information using techniques like observation and commentary. 3) "Fly on the wall" documentaries film events without the subjects' awareness, like Big Brother, capturing natural reactions.