IaaS (Infrastructure as a Service)

IaaS (Infrastructure as a Service) is the most basic cloud ✕ "The cloud" refers to services and storage that run not on your device but on external servers on the internet. You can access them from anywhere. More in the glossary → model: instead of buying and maintaining physical servers, you rent the fundamental resources — computing power, storage and networking — over the internet and pay only for what you use. The provider looks after the hardware and the data centre, while you manage the operating system, the applications and the data, with a lot of configuration freedom. Examples are Amazon EC2, Google Compute Engine or Azure virtual machines. It is the most flexible and scalable option — you can scale resources up or down in minutes — but also the one that demands the most technical know-how. It is often the foundation on which PaaS ✕ PaaS gives developers a ready-made cloud environment to build and deploy applications, without having to set up or maintain the servers underneath. More in the glossary → and SaaS ✕ SaaS is software you use over the internet on a subscription, hosted by the provider: you log in from the browser, with nothing to install and no updates or servers to worry about. More in the glossary → are built.