Platform as a service (PaaS) is a model for running applications without having to maintain the hardware and software infrastructure. PaaS applications also have the latest features without the pain of constantly having to upgrade them on individual computers.
Platform as a service (PaaS) is a complete development and deployment environment in the cloud, with resources that enable you to deliver everything from simple cloud-based apps to sophisticated, cloud-enabled enterprise applications. You purchase the resources you need from a cloud service provider on a pay-as-you-go basis and access them over a secure Internet connection.