Mycology is the science of studying fungi, their taxonomy, genetic,and biochemical properties. 

Mushrooms are the above ground spore-producing fruit bodies of fungi which are found on wood, leaves, grass or on the ground. 

The term mushroom refers to gilled mushrooms which have or lack a stem. It is used also to describe all macro-fungi, including puffballs, stinkhorns, toothed fungi, polypores, boletes, chanterelles, Lactarius, coral. mushrooms, etc. Finally, it can refer to the entire organism, including the mycelium, which is always present and takes up the most space. In fact, not all fungi produce fruiting bodies with spores to distribute in new places. Some, having lost the ability to produce mushrooms, simply propogate by growing and moving through the soil. The largest mushroom in western US.

Other species of fungi include bread mods, single celled yeasts and sea fungi.

There is also the fungi/lichen association.

Where are they: Everywhere - in the Arctic - the Tropics and in between.In the oceans, rivers,, associated with trees and other plants, take up an immensely varied lifestyle, They are even on ourselves and we breathe in their spores with every breath. Mostly they have been and are being used for good purposes, though some are pathogens on humans and other animals; They have been attributa; to crop failures and food shortages.

Why study fungi?