PaaS

Platform as a Service (PaaS): A cloud service that provides a computing platform for web application developers. This can include both ready-to-use runtime environments (typically for web applications) and development environments that can be used with minimal administrative effort and without the need to purchase the underlying hardware and software. They support the entire software lifecycle, from design through development, testing, and deployment to the operation of web applications over the Internet. PaaS offerings are built on a scalable infrastructure (IaaS) of storage and computing power and can therefore also scale. Software as a Service (SaaS) offerings can be built on top of a PaaS environment. Thus, PaaS is the middle layer in the cloud stack between IaaS and SaaS.