Platform as a service (PaaS) is a category of cloud computing services that provides a platform allowing customers to develop, run, and manage applications without the complexity of building and maintaining the infrastructure typically associated with developing and launching an app.
Multi tenant environments
Highly scalable multi tier architecture
1. IaaS is the delivery of technology infrastructure as an on demand scalable service.
2. Usually billed based on usage
3. Usually multi tenant virtualized environment
4. Can be coupled with Managed Services for OS and application support