A 19-inch rack is a standardized frame used to hold electronic equipment, such as servers, switches, and routers. The term "19-inch" refers to the width of the equipment that fits into the rack, which is 19 inches across. These racks are commonly used in data centers and telecommunications facilities to organize and manage hardware efficiently. The design of 19-inch racks allows for easy installation and maintenance of equipment. They typically have mounting rails that support various devices, and they can be stacked or mounted in cabinets. This standardization helps ensure compatibility among different manufacturers and simplifies the setup of complex systems.