Edible mushrooms

Edible mushrooms are the fleshy fruit bodies  of numerous species of macrofungi (fungi  that bear fruiting structures large enough to be seen with the naked eye). Edibility may be defined by criteria including the absence of poisonous effects on humans and desirable taste and aroma. Mushrooms that have a particularly desirable taste are described as "choice". Edible mushrooms are consumed for their nutritional and culinary value. Mushrooms, especially dried shiitake, are sources of umami flavor.

A wide variety of edible mushrooms being sold by a vendor in San Juan Sacatepequez, Guatemala
To ensure safety, wild mushrooms must be correctly identified before their edibility can be assumed. Deadly poisonous mushrooms that are frequently confused with edible mushrooms include several species of the genus Amanita, particularly A. phalloides, the death cap. Some mushrooms that are edible for most people can cause allergic reactions  in others; old or improperly stored specimens can go rancid and cause food poisoning.[1] Additionally, mushrooms can absorb chemicals within polluted locations, accumulating pollutants and heavy metals  including arsenic and iron—sometimes in lethal concentrations.
Several varieties of fungi contain psychedelic  compounds—the magic mushrooms—while variously resembling non-psychoactive  species. The most commonly consumed for recreational use are Amanita muscaria (the fly agaric) and Psilocybe cubensis, with the former containing alkaloids such as muscimol  and the latter predominately psilocybin.
Edible mushrooms include many fungal species that are either harvested wild or cultivated. Easily cultivated and common wild mushrooms are often available in markets; those that are more difficult to obtain (such as the prized truffle, matsutake, and morel) may be collected on a smaller scale and are sometimes available at farmers' markets or other local grocers. Despite long-term use in folk medicine, there is no scientific evidence  that consuming "medicinal mushrooms" cures or lowers the risk of human diseases.