Cloud storage is a service model in which data is maintained, managed and backed up remotely and made available to users over a network (typically the Internet. Complete How-to Guide to Cloud Storage Thinking about making a move to the cloud? Explore this guide to discover the key considerations you need to know before taking the plunge, including public vs. private vs. hybrid cloud storage options, 8 questions to ask before using cloud storage and more. There are three main cloud storage models: Public cloud storage services, such as Amazon's Simple Storage Service (S3), provide a multi-tenant storage environment that’s most suitable for unstructured data. Private cloud storage services provide a dedicated environment protected behind an organization’s firewall. Private clouds are appropriate for users who need customization and more control over their data. Hybrid cloud storage is a combination of the other two models that includes at least one private cloud and one public cloud infrastructure. An organization might, for example, store actively used and structured data in a private cloud and unstructured and archival data in a public cloud. An enterprise-level cloud storage system should be scalable to suit current needs, accessible from anywhere and application-agnostic. See also: storage as a service (SaaS), cloud computing, cloud backup, utility storage, storage service provider (SSP).