What is cloud computing? Computing as a service over the Internet Cloud computing, often referred to as simply “the cloud,” is the delivery of on-demand computing resources—everything from applications to data centers—over the Internet on a pay-for-use basis. Software as a service (SaaS) Cloud-based applications—or software as a service—run on distant computers “in the cloud” that are owned and operated by others and that connect to users’ computers via the Internet and, usually, a web browser. IBM Cloud software as a service THE BENEFITS OF SAAS You can sign up and rapidly start using innovative business apps Apps and data are accessible from any connected computer No data is lost if your computer breaks, as data is in the cloud The service is able to dynamically scale to usage needs Platform as a service (PaaS) Platform as a service provides a cloud-based environment with everything required to support the complete lifecycle of building and delivering web-based (cloud) applications—without the cost and complexity of buying and managing the underlying hardware, software, provisioning and hosting. Infrastructure as a service (IaaS) Infrastructure as a service provides companies with computing resources including servers, networking, storage and data center space on a pay-per-use basis. Public cloud Public clouds are owned and operated by companies that offer rapid access over a public network to affordable computing resources. With public cloud services, users don’t need to purchase hardware, software or supporting infrastructure, which is owned and managed by providers. Private cloud A private cloud is infrastructure operated solely for a single organization, whether managed internally or by a third party, and hosted either internally or externally. Private clouds can take advantage of cloud’s efficiencies, while providing more control of resources and steering clear of multi-tenancy. Hybrid cloud A hybrid cloud uses a private cloud foundation combined with the strategic integration and use of public cloud services. The reality is a private cloud can’t exist in isolation from the rest of a company’s IT resources and the public cloud. Most companies with private clouds will evolve to manage workloads across data centers, private clouds and public clouds—thereby creating hybrid clouds.