Cloud

Cloud, or cloud computing, is a model of delivering IT resources — computing power, storage, databases and applications — over the internet, on demand and billed by actual usage. Instead of buying and maintaining their own servers, users rent the resources they need from a cloud provider and scale them according to current demand. The cloud removes the burden of managing physical infrastructure from the organization.

How cloud computing works

The foundation of the cloud is virtualization, which allows many isolated virtual machines to run on a single physical server. The provider maintains distributed data centers, and management software allocates resources and moves workloads between machines. As a result, the service stays available even when a single server fails.

The cloud is divided into three main service models. IaaS (Infrastructure as a Service) provides raw infrastructure: virtual machines, networking and storage. PaaS (Platform as a Service) adds a ready environment for running applications. SaaS (Software as a Service) delivers finished software in the browser.

Practical applications

The cloud model shines in projects with variable load and where launch speed matters.

• Elastic scaling — an online store can add resources during a campaign and reduce them afterward.
• Backups and disaster recovery — data replicated across data centers protects against loss.
• Fast deployments — a new environment spins up in minutes, with no hardware purchase.

Cloud computing has become a foundation of modern IT and, for many companies, a natural complement to or alternative to a classic dedicated server. Hybrid models that combine on-premises resources with the public cloud are also increasingly popular.