Platform as a Service involves the consumer deploying software applications onto the cloud infrastructure and running them there, however large or small they may be, thereby avoiding any CapEx (capital expenditure) on servers or infrastructure; the platform is usually scalable and elastic so that as usage peaks or dips, the platform automatically expands or contracts to meet the need. Programming platforms and tools (such as .NET, java or python) and APIs for building cloud-based applications and services are exposed to developers who can create applications for testing or for commercial purposes for a minute fraction of the cost of provisioning server infrastructure for themselves. Google’s App Engine allows developers to write programs to run on Google’s infrastructure or platform. Other examples include Amazon Simple Storage Service (S3), Azure Storage, and Force.com.