Dye-sensitized solar cells (DSSCs) are photovoltaic devices that utilize the synergistic interaction between photosensitive dyes and wide-bandgap semiconductors. Unlike conventional semiconductor-based absorption mechanisms, DSSCs harvest light through molecular dyes anchored onto nanostructured photoanodes, achieving power conversion efficiencies exceeding 12%. These devices operate under mild fabrication conditions, exhibit excellent compatibility with flexible or transparent substrates, and maintain stable performance under low-light irradiation. The core architecture comprises four functional components: the photoanode—typically nanoporous metal oxides that offer high surface area for dye loading and electron transport; the dye sensitizer—organic or metal-complex molecules that absorb photons and inject excited electrons into the semiconductor conduction band; the electrolyte—a redox-active medium that regenerates oxidized dye molecules and conducts holes to the counter electrode; and the counter electrode—composed of catalytic materials such as platinum or carbon, which facilitate charge transfer within the redox system. Despite their unique advantages, DSSCs face performance constraints due to narrow dye absorption spectra, interfacial charge recombination, and electrolyte instability. Advances in dye molecular design, interface passivation, and solid-state electrolyte development are crucial for further efficiency enhancement and device durability. Owing to their semi-transparency, mechanical flexibility, and color tunability, DSSCs are particularly suitable for indoor photovoltaics, curved architectural glazing, portable electronics, and Internet of Things (IoT) sensors. While their efficiency remains lower than silicon- and perovskite-based cells, their low production cost and superior low-intensity light harvesting offer distinct advantages for decentralized energy applications.