During the last two decades, by using a combination of both chalcogens (sulfur (S), selenium (Se), tellurium (Te), and polonium (Po)) and other elements like silicon (Si) and germanium (Ge), a huge number of chalcogenide glasses (ChGs) were prepared and studied. Compared to oxide-based glassy materials, ChGs have unique properties and functionalities which make them suitable for photonic applications. These materials are transparent in nature from the visible to the near-infrared region and can be used for the preparation of optical and electronic devices like ChG fibers, optical switches, sensors, and phase change memorizers. This chapter deals with some basics of ChGs, preparation techniques and a review of the latest technological development. The structural properties, optical properties, thermal and electrical properties of ChGs have been discussed. The physical aging effect has been explored. In the second part of this chapter, the applications of ChGs especially in dye sensitized solar cells (DSSCs), semiconductors, electrical memories and phase change memories have been discussed.