Exploitation movie

Exploitation movie is a label that is applied to certain movies: These usually have a low budget, and focus on showing either violence or sex. Very often, they try to be successful by following a trend. Sometimes they are produced for a niche of the market. In almost all cases, exploitation movies fall in the category B-movies. Sometimes, exploitation movies attract a cult following they get the attention of the movie critics. Some of these movies set trends, and become important. An example of such a movie is Night of the Living Dead, of 1968. 
The term "exploitation" is defined very loosely: it is more about the viewers' impression that this exploitation happens, than the people actually being exploited. The first exploitation movies appeared in the 1920s. Exploitation movies only became popular after the 1960s and 1970s, when there was less censorship. Very often, exploitation movies use recent news events to base their story on. Major film studios ofen avoid such events, because producing the movie takes a long time and a lot of money. 
In 1938, Orson Welles produced War of the Worlds to be broadcast on radio, as a Halloween special. When it was aired, this shocked many Americans. As a result, Universal Pictures edited one of their Flash Gordon serials into a short movie which it released ot movie theatres one week after Welles' boradcast. The movie was called "Mars Attacks the World."