Cloud computing involves programs and applications running simultaneously on connected computers over a network. There are three main cloud service models: infrastructure as a service, platform as a service, and software as a service. Some well-known cloud vendors providing these services include Google, Amazon, IBM, Oracle Cloud, Rackspace, Salesforce, Zoho and Microsoft Azure.

1. Prepared by
Sajal

2.  Cloud computing involves distributed computing over a network, where a
program or application may run on many connected computers at the same
time. It specifically refers to a computing hardware machine or group of
computing hardware machines commonly referred as a server connected
through a communication network such as the Internet an intranet a local
area network (LAN) or wide area network (WAN). Any individual user who has
permission to access the server can use the server's processing power to run
an application, store data, or perform any other computing task.
The major models of cloud computing service are known as software as a
service,platform as a service, and infrastructure as a service. These cloud
services may be offered in a public, private or hybrid network.[ Google,
Amazon, IBM, Oracle Cloud, Rackspace, Salesforce, Zoho and Microsoft
Azure, Drof Box are some well-known cloud vendors.[

3. Infrastructure as a service (IaaS)
Platform as a service (PaaS)
Software as a service (SaaS)
Security as a service (SECaaS)

4. Cloud computing relies on sharing of resources to achieve
coherence and economies of scale.
Cloud computing is probably the most cost efficient method to use,
maintain and upgrade. Traditional desktop software costs companies a lot
in terms of finance.
Almost Unlimited Storage
Backup and Recovery
Easy Access to Information

5. Users access cloud computing using networked client devices, such as
desktop computers, laptops, tablets and smart phones. Some of these
devices – cloud clients – rely on cloud computing for all or a majority of
their applications so as to be essentially useless without it. Examples are
thin clients and the browser-based Chromebook . Many cloud applications
do not require specific software on the client and instead use a web
browser to interact with the cloud application.

6. The development of the Internet from being document centric via semantic data
towards more and more services was described as "dynamic web".This contribution
focused in particular in the need for better meta-data able to describe not only
implementation details but also conceptual details of model-based applications.
Cloud vendors are experiencing growth rates of 50% per
annum.

7. Private cloud
Public cloud
Community cloud
Hybrid cloud
Distributed cloud

8. Privacy
Privacy solutions
Legal
Vendor lock-in
Security

9. According to Gartner's Hype cycle, cloud computing has reached a
maturity that leads it into a productive phase. This means that most
of the main issues with cloud computing have been addressed to a
degree that Clouds have become interesting for full commercial
exploitation. This however does not mean that all the problems
listed above have actually been solved, only that the according risks
can be tolerated to a certain degree. Cloud computing is therefore
still as much a research topic, as it is a market offering.