commodity hardware

Commodity hardware, in an IT context, is a device or device component that is relatively inexpensive, widely available and more or less interchangeable with other hardware of its type.

To be interchangeable, commodity hardware is usually broadly compatible and can function on a plug and play basis with other commodity hardware products. In this context, a commodity item is a low-end but functional product without distinctive features.  A commodity computer, for example, is a standard-issue PC that has no outstanding features and is widely available for purchase. 

Other examples of commodity hardware in IT:

• RAID (redundant array of independent -- originally inexpensive -- disks) performance typically relies upon an array of commodity hard disks to enable improvements in mean time between failures (MTBF), fault tolerance and failover.
• A commodity server is a commodity computer that is dedicated to running server programs and carrying out associated tasks. In many environments, multiple low-end servers share the workload. Commodity servers are often considered disposable and, as such, are replaced rather than repaired.

Generally, commodity hardware can arise from any technologically mature product in a mature market. That means that most hardware products that have been around for a long time are available in commodity versions, although they aren't generally marketed as such.