The fourth stage is pure simulation, in which the simulacrum has no relationship to any reality whatsoever. Here, signs merely reflect other signs and any claim to reality on the part of images or signs is only of the order of other such claims. This is a regime of total equivalency, where cultural products need no longer even pretend to be real in a naïve sense, because the experiences of consumers’ lives are so predominantly artificial that even claims to reality are expected to be phrased in artificial, “hyperreal” terms. Any naïve pretension to reality as such is perceived as bereft of critical self-awareness, and thus as oversentimental.
– Wikipedia entry on simulacra and simulations