A traditional narrative which conveys old ideas or belief systems. A myth is also a belief in a fictitious person, object or abstract concept. Myths are also called old wives tales and probably arose from the great historical unknowns that created fear. They can be perpetuated with poor education, politically incorrect language, fallacious thinking, memetic behaviour and the use of sayings.
In many places, targetted criticism of culturally entrenched myths is strictly forbidden. eg, religous ideology. This type of conduct is one of many social problems inhibiting freedom, free speech and democracy.
Perpetuating a myth can be self-serving. Myths can be exploited for personal gain by fraud and hoaxes. They also cause problems for debate because myths create false premises and extreme, irrational points of view. Myths can create stereotypes are allow for discrimination to go unchecked.