What is the concept behind Doomsday?

Doomsday is also known as the Day of Last Judgment, as pronounced by God. According to the New Testament, the Armageddon is the decisive battle between God and Satan, at the end of which a destructive effect will fall on Earth. The world will not be the same again, and the human race may not survive. There will be a total catastrophe on earth, leading to doom. God is also expected to pronounce decrees on humans.