There are three types of unsaturated hydrocarbons: alkenes, alkynes and aromatic hydrocarbons. Alkenes have one or more carbon-carbon double bond.Alkynes have one or more carbon-carbon triple bond, and aromatic hydrocarbons have a benzene or aromatic ring in their structure.ydrocarbons are compounds that only consist of the elements hydrogen and carbon. In this lesson, we will focus on one type of hydrocarbon: unsaturated hydrocarbons, and its three types-alkenes, alkynes and aromatic hydrocarbons.