IUPAC names follow the nomenclature conventions of the International Union of Pure and Applied Chemistry. These names describe the structures in detail (if one knows the conventions), but tend to be unwieldy.
In the IUPAC system, the carboxyl carbon is denotes by the number one, and positions in the chain are denoted with reference to it. E.g. a double bond is said to be at the 9-carbon if it originates at the ninth carbon, and extends to the next (tenth) carbon in the chain.