The Class Basidiomycetes is a large group of fungi characterized by the presence of a club-shaped structure known as a basidium. Some common synonyms for this class include the Agaricomycetes, which includes familiar species like mushrooms, toadstools, and bracket fungi, as well as the Urediniomycetes, which include rusts and smuts. The Basidiomycetes are an important group of fungi, playing key roles in decomposing organic matter and in forming mycorrhizal associations with plants. While many members of this class are beneficial, some are also destructive, causing diseases in plants or animals. Understanding the various synonyms for the Class Basidiomycetes can help to clarify the complex relationships within this diverse and fascinating group of fungi.