A data center (or datacenter) is a facility composed of networked computers and storage that businesses or other organizations use to organize, process, store and disseminate large amounts of data. A business typically relies heavily upon the applications, services and data contained within a data center, making it a focal point and critical asset for everyday operations.
Data centers are not a single thing, but rather, a conglomeration of elements. At a minimum, data centers serve as the principal repositories for all manner of IT equipment, including servers, storage subsystems, networking switches, routers and firewalls, as well as the cabling and physical racks used to organize and interconnect the IT equipment. A data center must also contain an adequate infrastructure, such as power distribution and supplemental power subsystems, including electrical switching; uninterruptable power supplies; backup generators and so on; ventilation and data center cooling systems, such as computer room air conditioners; and adequate provisioning for network carrier (telco) connectivity. All of this demands a physical facility with physical security and sufficient physical space to house the entire collection of infrastructure and equipment.
Data center consolidation and colocation
There is no requirement for a single data center, and modern businesses may use two or more data center installations across multiple locations for greater resilience and better application performance, which lowers latency by locating workloads closer to users.
Conversely, a business with multiple data centers may opt to consolidate data centers, reducing the number of locations in order to minimize the costs of IT operations. Consolidation typically occurs during mergers and acquisitions when the majority business doesn't need the data centers owned by the subordinate business.