What is the difference between aromatic hydrocarbons and aromatic compounds

The difference between aromatic hydrocarbons and aromatic compounds lies in the fact that aromatic hydrocarbons have hydrocarbon groups attached to the benzene ring (Ph-) (as shown in the figure), whereas aromatic compounds have the rest of the groups or atoms attached to the benzene ring (Ph-); essentially, aromatic hydrocarbons are a subset of aromatic compounds.

Aromatic hydrocarbons (aromatic hydrocarbons) is a general term for benzene and its derivatives, which refers to hydrocarbon compounds that contain one or more benzene rings in their molecular structure. The name comes from the fact that at the beginning of the development of organic chemistry, this class of compounds was almost always found in volatile, aromatic substances, and its nucleophilic substitution mechanism is shown in Figure:

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Aromatic hydrocarbons. Encyclopedia