Software as a Service (SaaS) – Access and use software that’s stored and maintained in the cloud, usually includes storing related files. It’s the most commonly used among the three.
Platform as a Service (PaaS) – Works as a platform on which software applications are developed.
Infrastructure as a Service (IaaS) – Allows businesses to create their own virtual data centers in the cloud. IaaS is typically used as a building block for developing and deploying PaaS and SaaS applications. It’s designed for ultimate control over all resources.