Cloud systems offer low cost access to huge computational, storage, and network resources. These systems offer per-user and per-application isolation and customization via a service interface that is often implemented using high-level language technologies, well-defined Application Programming Interfaces, and web services.
PaaS solution stacks provide all of the infrastructure to design or deploy general, business, social and enterprise level software applications without being concerned about the underlying infrastructure including networks, servers, operating systems, storage and all the programming tools & applications.