Author's Note.- Introduction.- Origins: Marine Environment - Terrestrial Environment - Extraterrestrial Environment Occurrence: Simple Alkanes - Simple Functionalized Acyclic Organohalogens - Simple Functionalized Cyclic Organohalogens - Terpenes - Steroids - Marine Nonterpenes - C15 Acetogenins - Iridoids - Lipids and Fatty Acids - Fluorine-Containing Carboxylic Acids - Prostaglandins - Furanones - Amino Acids and Peptides - Alkaloids - Heterocycles...