Cloud Computing
Cloud computing is the on-demand availability of computer system resources, especially data storage and computing power, without direct active management by the user.
Cloud computing is a model for delivering IT resources and services—such as computing power, storage, databases, networking, software, and analytics—over the internet ('the cloud') on a pay-as-you-go basis. Instead of owning and maintaining physical data centers and servers, users can access technology services from a cloud provider on an as-needed basis. The three main types of cloud services are Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). IaaS provides basic computing infrastructure (virtual machines, storage, networks), PaaS offers a platform for developing, running, and managing applications without the complexity of managing the infrastructure, and SaaS delivers ready-to-use software applications over the internet. Cloud computing offers significant benefits, including cost savings (pay only for what you use), scalability (easily scale resources up or down), speed and agility (deploy resources rapidly), global reach, and improved reliability and security managed by the provider. Major cloud providers include Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP).
graph LR
Center["Cloud Computing"]:::main
Pre_virtualization["virtualization"]:::pre --> Center
click Pre_virtualization "/terms/virtualization"
Center --> Child_iaas_infrastructure_as_a_service["iaas-infrastructure-as-a-service"]:::child
click Child_iaas_infrastructure_as_a_service "/terms/iaas-infrastructure-as-a-service"
Center --> Child_saas_software_as_a_service["saas-software-as-a-service"]:::child
click Child_saas_software_as_a_service "/terms/saas-software-as-a-service"
Center --> Child_serverless["serverless"]:::child
click Child_serverless "/terms/serverless"
Rel_edge_computing["edge-computing"]:::related -.-> Center
click Rel_edge_computing "/terms/edge-computing"
Rel_devops["devops"]:::related -.-> Center
click Rel_devops "/terms/devops"
Rel_content_delivery_network["content-delivery-network"]:::related -.-> Center
click Rel_content_delivery_network "/terms/content-delivery-network"
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🧠 Knowledge Check
🧒 Explain Like I'm 5
☁️ A way to use infinite computer power and storage over the internet, paying only for the minutes you actually use.
🤓 Expert Deep Dive
Cloud computing abstracts hardware and infrastructure layers, offering services through well-defined APIs and management consoles. The underlying architecture typically involves massive data centers utilizing virtualization technologies (e.g., hypervisors like KVM, Xen) to pool resources and enable multi-tenancy. Resource scheduling, load balancing, and automated provisioning are critical components for efficient operation and scalability. Deployment models include public clouds (shared infrastructure), private clouds (dedicated infrastructure), and hybrid clouds (a combination). Key architectural considerations involve data locality, network [latency](/en/terms/network-latency), security (shared responsibility model), compliance, and cost optimization strategies (e.g., reserved instances, spot instances). Serverless computing represents a further evolution, abstracting even the server management aspect, where code execution is event-driven and managed entirely by the provider. Trade-offs exist between control, cost, performance, and vendor lock-in. The economics of scale achieved by major providers allow for competitive pricing and advanced service offerings.