Polycyclic compounds are organic molecules that consist of multiple interconnected aromatic rings. These rings share common edges, creating a complex structure. Common examples include naphthalene and anthracene, which are used in various applications, including dyes and pharmaceuticals. The unique arrangement of atoms in polycyclic compounds often leads to interesting chemical properties, such as increased stability and distinct reactivity. Their structure can influence how they interact with other substances, making them important in fields like materials science and medicinal chemistry. Understanding these compounds is crucial for developing new materials and drugs.