The world is not ending. There are rumors spreading that the world will come to an end by the end of 2012. The belief is according to a 2012 phenomenon which comprises of a range of eschatological beliefs.
Everything needs to end sometime. The world is made up of perishable things - rivers dry up, trees die, people die . . . and so it only makes sense that at some point the world itself will die. The debate is WHEN this will happen. Many people say that it will end in December of 2012 based on the Mayan calendar. However, calculations that brought people to the 12/12 date are flawed because they did not take into account leap years and therefore the supposed "apocalypse" should have happened approximately 13 months ago.