Platform as a Service provides cloud based runtime environment for applications which offers tools for development and deployment that are required to develop applications. Some PaaS vendors provide point-and-click tools for non developers to develop web applications too.
PaaS vendors provide build-in APIs for developers to use. Applications that are hosted on PaaS can be accessed form any where anytime. All you need is a PC and Internet connection. Applications on cloud can be scaled to fit the number of users without doing any change to the application. This simplifies the burdon that should behandled by a developer.
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| Google App Engine (PaaS) |
However applications that are hosted on PaaS platform are vendor-lock. Although applications are developed using standard programming languages, the APIs that are used on platforms differs from vendor to vendor.
The best Platform as a Service vendors are as follows;
- Google (Google App Engine)
- Salesforce.com
- Microsoft Azure
- Openshift