Definition
Cloud hosting runs your site or app on a distributed network of virtual servers spread across multiple physical machines and often multiple regions, rather than one dedicated box. Providers meter CPU, RAM, storage and bandwidth in near real time, often billing by the second or minute, so you pay only for what you use and can scale resources up or down automatically as demand shifts. This gives better redundancy than single-server hosting (if one node or availability zone fails, another takes over), absorbs traffic spikes without manual intervention, and is the default choice for applications that need high availability or unpredictable scaling. The major cloud platforms are AWS, Microsoft Azure and Google Cloud, each offering dozens of regions and availability zones; managed providers like Cloudways, DigitalOcean App Platform and Render layer simpler interfaces on top so you skip most infrastructure management. It is unnecessary, and often costlier, for simple sites that run fine on shared hosting or a single VPS.
How it works
Underneath, cloud hosting is virtual machines and managed services running on huge fleets of physical hardware spread across regions and availability zones. You either rent virtual machines and manage them yourself (IaaS), or use platform services (PaaS) that abstract the OS away.
Why it matters
Cloud hosting is the right choice when you need automatic scaling, high availability, or specific managed services (queues, databases, AI inference). It is overkill (and expensive) for simple sites that would be fine on shared or VPS. The unpredictability of usage-based billing is the main risk; set spending alerts.