What is cloud computing? What types of services are provided by cloud computing?

The clouds can be big and small, changeable, can be blinding the sun, bringing stormy, it can be a blue sky with floating white clouds, while dispersed, while gathered again. Cloud computing, as its name implies, is capable of providing powerful computing power and is able to scale and aggregate computing power.

The reason why cloud computing, I think there are three reasons, one is the progress of science and technology, the processing power of ordinary PC servers far more than the previous minicomputer, resulting in very low utilization of system resources, the development of parallel computing technology, hundreds of units , Thousands, and even tens of thousands of PC server processing power to replace the mainframe, midrange machine functions; Second, ecological awareness, awareness of energy saving and environmental protection will be a large number of centralized management of PC servers together, on time and on-demand to provide the appropriate Processing capacity, the demand for small business from a single server, part of the CPU, memory and other resources, the demand for the business will be a number of servers together to use, the use of complete release of resources; Third, the rise of the Internet, for consumers to buy Service provides a convenient way. Further, software capabilities running on hardware can be scaled down and aggregated to further enrich cloud computing content.

Baidu's definition of cloud computing is a pay-per-use model that provides available, convenient, on-demand network access to configurable computing resource pools (resources including networks, servers, storage, applications Software, services, these resources can be quickly provided, with minimal administrative effort or little interaction with service providers.

Cloud computing provides three forms of services:

Infrastructure-as-a-Service (IaaS): Infrastructure-as-a-Service is cloud service of hardware resources such as CPU, storage and network,

PaaS (Platform-as-a-Service): Platform-as-a-Service is the software capability of running software and the software capability of developing software, which is provided to consumers as services such as the development platforms of Alibaba and Tencent.

SaaS (Platform-as-a-Service): Software-as-a-Service (SOA), which clouds the capabilities of applications and serves as a service to consumers such as Taobao, Jingdong, etc.