There are public, private, and hybrid cloud solutions. Public cloud models are the most common. They are a cloud infrastructure that can be accessed from anywhere and stored in many servers rather than a single one. Usually, public clouds have several clients, all using the cloud service. But the cloud infrastructure is owned by the cloud services provider. Private cloud models are more specialized, private, and expensive. While it's still cloud-based (multiple computers sharing resources), only one client uses the cloud; this increases security. In this model, the private cloud operates much like a private server would. But unlike a private server, there are multiple computers, creating stability and redundancy. Finally, some hybrid models involve both public and private clouds, which work together to create a blend of efficiency and security. Some applications are stored on the public (shared) cloud in this model, while others are stored in the private (not-shared) cloud.