What is $IUPAC$ (modern) and common method for nomenclature of organic compounds?

(N/A) Nomenclature by $IUPAC$ method: Organic chemistry deals with millions of compounds. In order to clearly identify them,a systematic method of naming has been developed and is known as the $IUPAC$ system of nomenclature.
- $IUPAC$ stands for International Union of Pure and Applied Chemistry.
- Sometimes $IUPAC$ names are lengthy and complicated,so common names are used.
- In this systematic nomenclature,the names are correlated with the structure such that the reader or listener can deduce the structure from the name.
$(B)$ Trivial (common) nomenclature method: Organic compounds were assigned names based on their origin or certain properties.
- e.g.,Citric acid is named so because it is found in citrus fruits.
- The acid found in red ants is named formic acid since the Latin word for ant is $formica$.
- These names are traditional and are considered as trivial or common names.
- Some common names are followed even today. For example,Buckminster fullerene is a common name given to the newly discovered $C_{60}$ cluster (a form of carbon) noting its structural similarity to the geodesic domes popularized by the famous architect $R$. Buckminster Fuller.