A server rack is a standardized frame or enclosure designed to hold multiple servers and other computing equipment. These racks help organize hardware, optimize space, and improve airflow for cooling. They are typically made of metal and come in various sizes, with the most common being 19 inches wide. In a data center, server racks are essential for housing equipment like network switches, storage devices, and patch panels. Each rack can accommodate several units of equipment, measured in rack units (U), where one unit is 1.75 inches high. This organization allows for efficient management and maintenance of technology infrastructure.