Division (Phylum) Ascomycota:
Sac fungi. Sometimes you hear this one called ascomycetes. But it tends to leave its spors in a sac or ascus. Common fungi in Ascomycota include Dutch Elm disease, truffles, fungus that cuases rye smut, Baker's yeast, Brewer's yeast, yeast that causes infection and diaper rash.
Commonly called the "Sac Fungi" because spores are produced in sac-like structures called asci, this division contains over 60,000 species of fungi, including many which are important in the food industry. Gourmet delicacies like the morels and truffles as well as the unicellular yeast (which are used in the prep of bread and beer) are ascomycetes. More include fungus that causes Dutch Elm Disease and the Chestnut Blight, along with Penicillium and Aspergillis.