The simplest n-alkane is methane CH4, which is also the simplest organic matter. "N-alkanes" in industry usually refer to a mixture of a series of saturated hydrocarbons, also known as "paraffin oil (Liquid Paraffin)", "light paraffin" and "heavy paraffin", which are completely different from the chemical definition we mentioned. The longer the carbon chain of n-alkanes, the more likely isomers appear. Therefore, it is more and more difficult to prepare pure linear alkanes.