**IT infrastructure** refers to the composite set of hardware, software, networks, facilities, and related services that form the foundation for the delivery and operation of [[Information technology|information technology]] services within an organization. It encompasses the physical and virtual components required to support [[IT service|IT services]] and [[Business process|business processes]], including [[Server (computing)|servers]], [[Computer network|networking equipment]], [[Storage device|storage systems]], [[Operating system|operating systems]], [[Middleware|middleware]], [[Data center|data centers]], and the power and cooling systems that sustain them. IT infrastructure is a core concern of [[IT service management|IT service management]] (ITSM) disciplines and is typically managed and documented through [[Configuration management|configuration management]] practices. IT infrastructure components are broadly categorized into compute, storage, and networking resources. [[Computer|Compute]] infrastructure includes the physical or virtual [[Processor|processors]] and memory that execute workloads, encompassing [[Mainframe computer|mainframes]], [[Rack server|rack servers]], [[Blade server|blade servers]], and [[Virtual machine|virtual machines]]. [[Computer data storage|Storage]] infrastructure comprises systems for persisting data, including [[Storage area network|storage area networks]] (SANs), [[Network-attached storage|network-attached storage]] (NAS), and [[Object storage|object storage]] platforms. [[Computer network|Network]] infrastructure provides the connectivity fabric that links these components, including [[Router|routers]], [[Network switch|switches]], [[Firewall (computing)|firewalls]], [[Load balancer|load balancers]], and [[Wide area network|wide area network]] (WAN) links. Supporting facilities such as [[Data center|data centers]] provide the physical environment, including [[Power supply|power]], cooling, and physical security, necessary to operate these components reliably. The delivery model for IT infrastructure has undergone significant transformation with the widespread adoption of [[Cloud computing|cloud computing]]. Traditional [[On-premises software|on-premises]] infrastructure, in which organizations own and operate their own physical hardware, has been increasingly supplemented or replaced by [[Infrastructure as a service|infrastructure as a service]] (IaaS) offerings from providers such as [[Amazon Web Services|AWS]], [[Microsoft Azure|Azure]], and [[Google Cloud Platform|Google Cloud]], which provide compute, storage, and networking resources on demand over the internet. [[Hybrid cloud|Hybrid cloud]] architectures combine on-premises and cloud-hosted infrastructure, while [[Multi-cloud|multi-cloud]] strategies distribute workloads across multiple cloud providers. The rise of [[Software-defined networking|software-defined networking]] (SDN), [[Hyperconverged infrastructure|hyperconverged infrastructure]] (HCI), and [[Infrastructure as code|infrastructure as code]] (IaC) practices has further changed how infrastructure is provisioned, configured, and managed, enabling greater automation and programmability across the infrastructure lifecycle.