Many simple aromatic rings have trivial names.
They are usually found as substructures of more complex molecules ("substituted aromatics").
Typical simple aromatic compounds are benzene, indole, and pyridine.
They can be monocyclic as in benzene, bicyclic as in naphthalene, or polycyclic as in anthracene.
In contrast, molecules with 4n pi electrons are antiaromatic.