Eschatology refers to religious end of the world scenarios, or more broadly the concept is secularized and used to refer to potential environmental catastrophes, wars, terrorism and other events that could literally or metaphorically could be said to bring about the end of the world or a similarly nighmarish scenario. Eschatology as an academic field is a subdiscipline of religious studies concerned with the study of beliefs and doctrines about religious end of the world scenarios.
In certain strains of evangelical Christianity, the end of the world is preceded by the Rapture, an event during which "the dead in Christ shall rise... [then] we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air" (1 Thes. 4:15-17).
Many preachers claim to know when the end of the world is happening, and a number of sects have been formed around shared eschatological beliefs. In contemporary American society, eschatological religious beliefs have been promoted through popular media including television (Hal Lindsey, who predicted the end of the world in the 1980s and in 2000, has had shows on Christian television networks), novels (the Left Behind series) and the Internet (with websites like Rapture Ready). Critics of these (mostly dispensationalist) promoters of the end of the world point to the statements of Jesus in Matthew 24:36 ("But of that day and hour knoweth no man, no, not the angels of heaven, but my Father only." - KJV) and the equivalents in Mark 13:32 and Acts 1:7.
Critics of eschatological evangelists and preachers also point to the long history of failed end-of-the-world predictions and to the cognitive defence mechanisms employed by advocates and followers of failed predictions to reinterpret those failures.