A tin foil hat is a hat made from one or more sheets of tin foil or aluminium foil, or a piece of conventional headgear lined with foil, often worn in the belief or hope that it shields the brain from threats such as electromagnetic fields, mind control, and mind reading. The notion of wearing homemade headgear for such protection has become a popular stereotype and byword for paranoia, persecutory delusions, and belief in pseudoscience and conspiracy theories.
"Tin foil" is a common misnomer for aluminium foil in English-speaking countries; packaging metal foil was formerly made out of tin before it was replaced with aluminium.[1]
- ^ "Foil - metallurgy". Britannica.com. Encyclopædia Britannica. Retrieved 17 July 2016.