What is a server?
2026-10-28
A server is a hardware or software system that provides computing resources, data, or application functionality to users over a network. In the context of data centers, the term usually refers specifically to a physical system.
A physical server contains one or more central processing units (CPUs), RAM, network interfaces for data exchange, magnetic and/or solid-state storage devices, and input/output controllers. It may also include redundant power supplies, remote-management tools such as a Baseboard Management Controller (BMC), and hardware-monitoring systems.
Unlike personal computers and workstations, servers are designed for continuous 24/7/365 operation and for serving large numbers of users simultaneously. Their architecture therefore supports the hot-swapping of certain components—replacing them without shutting down the entire system. This is standard for power supplies, cooling fans, and storage drives. In some enterprise-grade systems, network cards and memory modules can also be hot-swapped; hot-swappable CPUs are extremely rare and available only in specialized high-end systems. In recent years, servers have increasingly been equipped with graphics processing units (GPUs), which accelerate applications such as artificial intelligence, machine learning, scientific computing, and data analytics.