Interestingly, the word fungus comes directly from Latin fungus that literally means mushrooms, and in turn comes from Greek sponge. Fungi are a separate class of microorganisms that reproduce from spores, and are thus different from plants that require photosynthesis to make food for themselves. Fungi consist of molds, yeast, mildew, and mushrooms. It can be unicellular or multi cellular. Mushrooms are fruiting bodies of some kinds of fungi, and most common or famous of these are those that have a button like structure with a stem. Mushrooms are both edible as well as non edible or poisonous.