Exploitation film is an informal label which may be applied to any film which is generally considered to be low budget, and therefore apparently attempting to gain financial success by "exploiting" a current trend or a niche genre or a base desire for lurid subject matter. The term "exploitation" is common in film marketing for promotion or advertising in any type of film. These films then need something to exploit, such as a big star, special effects, sex, violence, or romance. An "exploitation film", however, due to its low budget, relies more heavily than usual on "exploitation". Very often, exploitation films are widely considered to be of low quality, and are generally "B movies". Even so, they sometimes attract critical attention and cult followings. Some films which might readily be labeled as "exploitation films" have become trend setters and of historical importance in their own right, such as Night of the Living Dead (1968). Some films also might be advertised by the producers themselves as "exploitation films" in order to pique the interest of those who seek out films of this type.