PaaS

Platform as aService: A cloud service that provides a computing platform for web application developers. These can be both rapidly deployable runtime environments (typically for web applications) but also development environments that can be used with little administrative effort and without purchasing the underlying hardware and software. They support the entire software life cycle from design to development, testing, delivery and operation of web applications over the internet. PaaS offerings build on a scalable infrastructure (IaaS) of storage and computing power and can thus also scale. Building on a PaaS environment, Software as a Service (SaaS) offerings can emerge. Thus, PaaS is the middle layer in the cloud stack between Iaas and SaaS.