Fungi are eukaryotic, heterotrophic organisms with cell wall of chitin. They are mostly multicellular and filamentous (exception: yeast is unicellular and non-filamentous). Their body consists of long, slender thread-like structure is called hyphae. The network of hyphae is known as mycelium. Hyphae may be septate or coenocytic based on the presence or absence of septae or cross wall in the hyphae.
Fungi are mostly saprophytes , some are parasites; and few are symbionts.
Phycomycetes, Ascomycetes, Basidiomycetes and deuteromycetes are the four classes under this Kingdom.
