Public or Private or Hybrid Cloud

Public	Private	Hybrid
Services are offered over the public internet and available to anyone who wants to purchase them.	A private cloud consists of computing resources used exclusively by users from one business or organization.	A hybrid cloud is a computing environment that combines a public cloud and a private cloud by allowing data and applications to be shared between them.
The cloud resources such as servers and storage are owned and operated by a third-party cloud service provider and delivered over the internet.	It can be physically located at your organization’s on-site datacenter, or it can be hosted by a third-party service provider. It uses an abstraction platform to provide cloud-like services such as Kubernetes clusters or a complete cloud environment like Azure Stack.	When computing and processing demand fluctuates, hybrid cloud computing gives businesses the ability to seamlessly scale their on-premises infrastructure up to the public cloud to handle any overflow - without giving third-party datacenters access to the entirety of their data. Organizations gain the flexibility and computing power of the public cloud for basic and non-sensitive computing tasks, while keeping business-critical applications and data on-premises, safely behind a company firewall.
Services may be free or sold on demand, allowing customers to pay only per usage for the CPU cycles, storage, or bandwidth they consume.	The organization is responsible for the purchase, configuration, and maintenance of the hardware. Communication between the systems is usually on the network infrastructure that the business owns and maintains.	Companies pay only for resources they temporarily use instead of having to purchase, program, and maintain additional resources and equipment that could remain idle over long periods of time.
Azure, AWS
Public clouds can be deployed faster than on-premises infrastructures and with an almost infinitely scalable platform.	A private cloud can provide more flexibility to an organization. Your organization can customize its cloud environment to meet specific business needs.	Hybrid cloud allows your organization to control and maintain a private infrastructure for sensitive assets. It also gives you the flexibility to take advantage of additional resources in the public cloud when you need them.
·       Service consumption through on-demand or subscription model: The on-demand or subscription model allows you to pay for the portion of CPU, storage, and other resources that you use or reserve. ·       No up-front investment of hardware: No requirement to purchase, manage, and maintain on-premises hardware and application infrastructure. The cloud service provider is held responsible for all management and maintenance of the system. ·       Automation: Quickly provision infrastructure resources using a web portal, scripts, or via automation. ·       Geographic dispersity: Store data near your users, or in desired locations without having to maintain your own datacenters. ·       Reduced hardware maintenance: The service provider is responsible for hardware maintenance.	·       Pre-existing environment: An existing operating environment that can't be replicated in the public cloud. A large investment in hardware and employees with solution expertise. A large organization may choose to commoditize their computing resources. ·       Legacy applications: Business-critical legacy applications that can't easily be physically relocated. ·       Data sovereignty and security: Political borders and legal requirements may dictate where data can physically exist. ·       Regulatory compliance / certification: PCI or HIPAA compliance. Certified on-premises datacenter.	·       Existing hardware investment: Business reasons require that you use an existing operating environment and hardware. ·       Regulatory requirements: Regulation requires that the data needs to remain at a physical location. ·       Unique operating environment: Public cloud can't replicate a legacy operating environment. ·       Migration: Move workloads to the cloud over time.