Cloud Computing harnesses the flexibility of the internet to replace cumbersome on-premises IT infrastructure with hosted services delivered on an as-needed basis. These services are generally available as infrastructure as a service (IaaS), platform as a service (PaaS) and software as a service (SaaS).

Cloud computing services can be delivered via a public cloud, private cloud or hybrid cloud. A public cloud is a provider that sells services to anyone on the internet. A private cloud is a network or a data center that supplies hosted services to a specific organization or limited customer base. A hybrid cloud combines the flexibility of a public cloud with the added security of a private cloud.

With IaaS cloud computing, companies can access servers, software, storage and networking equipment as a fully outsourced service. IaaS cloud providers generally bill services based on customer usage, giving customers the financial advantage of paying for only what they use.

With PaaS cloud computing, which is defined as a set of software and product development tools hosted on the provider’s infrastructure, developers construct applications on the provider’s platform over the internet.

With SaaS cloud computing, the vendor supplies the hardware infrastructure and software product and interacts with the customer through a front-end portal. Services can range from web-based email to inventory control and database processing. Because the service provider hosts both the application and the data, the end user is free to use the cloud computing service from anywhere, making SaaS a convenient choice for businesses ranging from small start-ups with a virtual office to large companies with global locations.