CONSPIRACY THEORIES
These are theories that exist to explain situations or events occurring as a result of plans secretly created by people or groups usually with power.
Conspiracy theories tend to resist falsification which means often is so evidence to prove or disprove the theory (as there is no evidence against it or for it). Because of this, conspiracy theories are more a matter of belief as opposed to something that is able to be proven or disproven.
The video below explains conspiracy theories in further detail and why conspiracy theories exist.
THE APPEAL OF CONSPIRACY THEORIES