Abstract
The first reports on chalcogen and/or chalcogenide glasses date from thebeginning of the XX century. However, it was only in the 1950s that started thesystematic study of chalcogenide glasses. Presently the research on this type of glassesis very active due to their great potential for practical use. The unique photoconductiveproperties, infrared transparency, ionic conduction, phase-change phenomenon andelectrical and thermal transport properties of chalcogenide glasses make them highlyattractive for a wide range of applications, from photoreceptors to high-density opticalmemories, infrared optical components, ionic sensors or thermoelectric devices.This chapter intends to give a brief overview on the uniqueness properties ofchalcogenide glasses. It starts with a picture of their structure and electronic structure,followed by their glass formation characteristics, a description of their physicalproperties and finalizing with a non-exhaustive presentation of their applications.