11H-Benzo[c]carbazole is a polycyclic aromatic hydrocarbon (PAH) consisting of a carbazole unit fused with an additional benzene ring. It serves as a fundamental building block in the field of organic electronics due to its rigid, planar, and conjugated structure, which facilitates efficient charge transport and luminescence. Its primary and most significant application is as a core structural unit for synthesizing advanced organic light-emitting diode (OLED) materials, particularly host materials for phosphorescent OLEDs (PhOLEDs). Derivatives of 11H-benzo[c]carbazole are engineered to possess high triplet energy levels, excellent thermal stability, and good charge carrier mobility, making them crucial for high-performance, energy-efficient display and lighting technologies. It is also explored in the development of organic semiconductors for other optoelectronic devices. As a key intermediate, it is extensively used in academic and industrial research to construct more complex heteroacene and ladder-type molecules aimed at improving device efficiency and longevity. Its synthesis and functionalization are active areas of research in materials chemistry.