Mold and mildew refer to tiny microscopic fungi that exist nearly everywhere. Fungi do not require light to survive, since they do not perform photosynthesis. Rather, they reproduce through microscopic spores. Mold and mildew often appear as brown, green or black spots, and usually cause a musty smell. Mold and mildew typically grow in damp locations, like basements and showers. Some common indoor molds include Alternaria, Cladosporium, Aspergillus and Penicillium. Mold Health Effects Fungus causes respiratory symptoms in some people, including coughing and wheezing. Other symptoms of exposure can include eye...