What is cloud computing?
Cloud computing includes the delivery of software, infrastructure, and storage over the Internet (either as separate components or a complete platform) based on user demand. You can think of it as a coherent, large-scale, publicly accessible collection of compute, storage, and networking resources, that are available for use in exchange for payment based on actual resources consumed. Data processing infrastructure – servers, storage, and bandwidth – can be procured from the cloud, consumed as needed, and then relinquished back to the cloud, all in a matter of minutes.
There are basically three
layers to cloud computing. Companies use them differently based on what they
offer. Cloud computing is often provided "as a service" over the
Internet, typically in the form of infrastructure as a service (IaaS), platform
as a service (PaaS), or software as a service (SaaS).