The term New World Order was used for a while after the end of the Cold War, including by former U.S. President George H. Bush, to refer to the results that the end of the Cold War would have on the international balance of power, including the hope that the end of the Cold War would usher in a new era of international co-operation through the United Nations. Closely related terms, the "New International Economic Order" and the "New International Information Order" were popular in the United Nations and its specialized agencies (especially UNESCO) in the 1970s and 1980s. They were used mainly by developing country groups (e.g. the G-77, the Non-Aligned Movement) to refer to the redistribution of wealth on a global scale, and the international control of the media to stop the "defamation" of third world countries. Western countries attacked these plans as an attempt to destroy capitalism and freedom of speech; and they were quitely dropped in the 1980s after Western countries threatened to withdraw from United Nations bodies. (The U.S. and U.K. made good this threat by withdrawing from UNESCO; the U.S. still has not rejoined.)
A rather different New World Order is the object of a belief or conspiracy theory among apocalyptic religious and political extremist groups, especially in the United States, that the United Nations has created a secret plan, known as the New World Order (NWO), to conquer the world. This would be part of the Apocalypse and the Second Coming with the UN and the federal government as agents of Satan.
There was the belief that this process would begin in 2000, set in motion by the predicted Y2K computer crisis causing widespread social disorder.
The understanding of these groups is that the NWO will be created by a military coup, using UN and American troops, against all the nations of the world to bring about the One World Government.
Under the NWO the following events will occur - The abolition of private property rights and gun ownership; all national and local elections controlled by the UN; the US constitution replaced by the UN charter (although clearly not the current UN charter); only approved religions will be allowed to exist - as parts of the One World Religion; home schooling will be illegal and there will be a UN approved curriculum; military bases will be turned into concentration camps to confine those who defy the NWO.
Although the UN is used as the motivator for these actions usually Jews, Communists, the Bilderberg Group, the Illuminati and similiar bodies are also often included in the conspiracy.