Types of Cloud Computing 

There are three relevant types of clouds: Private (internal or vendor hosted), Public (external), and Hybrid (mixed). Each cloud infrastructure has unique characteristics that can meet business objectives.

• Private: Private cloud (also called internal cloud or corporate cloud) is a computing architecture that provides hosted services to a limited number of people behind a security validation. For this higher security, most private computing is hosted from within the organizations. Hence, the organizations themselves have to “buy, build, and manage them" and thereby is not accepted by many as an actual cloud computing and subsequently do not even reap benefits from the major advantages of Cloud Computing.
• Public: A public cloud is actually the known version of Cloud and is based on the original cloud computing model. Here the service provider manages the resources including the applications and data storage and makes it available to the general public over the Internet. Generally the Public cloud service providers operate on a pay-per-usage model but some also provide free services till a certain limit to attract more users.
• Hybrid: Hybrid cloud as the name suggests is a composition of two or more clouds generally private and public. The individual cloud models remain independent entities but function together, thereby, offering the benefits of multiple deployment models. It sometimes is used in the reference of a platform where multiple cloud systems are connected and which offers the flexibility to move programs and data easily from one deployment system to another.