Conspiracy theories are a collection of the most popular unproven theories related but not limited to clandestine government plans, elaborate murder plots, suppression of secret technology and knowledge, and other supposed schemes behind certain political, cultural, and historical events. They did not have any link to the actual incidents. Some theories are meant to cover up the accusers' own schemes, such as the Holocaust denial. Most of them are imaginary works of some people.

        Conspiracy theories usually go against a consensus or cannot be proven using the historical method and are typically not considered to be similar to verified conspiracies such as Germany's pretense for invading Poland in World War II.