Paas (Platform-as-a-Service) is the next step in cloudisation after IaaS. IaaS hides hardware level and PaaS hides system software level.
In case you are using PaaS, you don’t need to care about operating system installation and updates. You just get an application server or database management system instances and can just deploy your application there.
Example PaaS:
- RedHat OpenShift
- Google App Engine
- Heroku
- Amazon Web Services (BeansTalk, RDS, CloudSearch, DynamoDB, S3, etc.)
- VMware vFabric
For sure there are a lot of operating systems, programming languages and databases, so I can hardly believe there is a PaaS that supports everything. Be sure to check that your programming language and database is supported by PaaS before start development.
Any PHP shared hosting is also a primitive PaaS which provides LAMP stack. Sometimes it supports not only PHP, but also Perl or Python. So the PaaS is not a new idea, it’s just a modern marketing buzz word.