Commonly, it is a misnomer for aluminium foil, as tin foil was commercially available before the aluminium counterpart, and some people continue to refer to the new product by the name of the old one.
Tin foil is stiffer than aluminium foil. It tends to give a slight tin taste to food wrapped in it, which is major reason why it has largely been supplanted by aluminium and other materials for wrapping food.
The Tinfoil Hat is the logical result of this profound insight, combining tinfoil's powerful mental shielding properties with the excellent counter-hexing effect of troll tears and the outstanding mind-focus powers of one of Azeroth's most precious gems.
The schematic for the Tinfoil Hat can be obtained by high-level characters from two faction-specific vendor NPCs in or around Area 52 that sell the schematic to anyone.
The only drawback is that the increased focus provided by the Tinfoil Hat may sometimes lead the wearer to achieve a superlative level of mental clarity, through which he can see the manifold subtle connections between seemingly unrelated facts and events, revealing to the wearer a much sharper image of the truth.
A tin-foil hat, also tinfoil hat, is a general term for a piece of headgear made from one or more sheets of tin foil, aluminum foil, or other similar material.
Some people wear the hats in the belief that they protect the brain from such influences as electromagnetic fields, or as a shield against mind control and/or mind reading.
A common high school physics demonstration involves placing an AM radio on tinfoil, and then covering the radio with a metal bucket.