Cloud computing is a model for delivering information technology (IT) services most commonly found in businesses that use subscription and billing management software. In this model, resources are made available to users over the Internet as a utility, like electricity or water. Instead of having IT infrastructure such as servers, storage, and software installed on-premises, cloud computing provides access to these resources as a shared pool of remote servers. This enables users to access these resources on-demand and pay only for what they use, rather than having to invest in and maintain their own infrastructure.
There are three main types of cloud computing services: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). In IaaS, cloud providers offer virtualized computing resources, such as virtual machines (VMs) and storage, which users can rent and configure as needed. In PaaS, cloud providers offer a platform for building, deploying, and running applications, without having to worry about the underlying infrastructure. SaaS is a model in which cloud providers offer complete software applications that users can access over the Internet, often with a subscription-based pricing model.