What is Cloud Computing?

Cloud computing is an emerging computing technology that uses the internet and central remote servers to maintain data and applications. Cloud computing allows consumers and businesses to use applications without installation and access their personal files at any computer with internet access. This technology allows for much more efficient computing by centralizing storage, memory, processing and bandwidth,In general..


* The cloud is a group of servers.
* A user interacts with the cloud without worrying about how it is implemented.
* The cloud company does all the magic

We use the cloud daily.
* Google
* Facebook
* Windows Live

Cloud computing comes into focus only when you think about what IT always needs: a way to increase capacity or add capabilities on the fly without investing in new infrastructure, training new personnel, or licensing new software. Cloud computing encompasses any subscription-based or pay-per-use service that, in real time over the Internet, extends IT's existing capabilities.

In general, cloud computing customers do not own the physical infrastructure, instead avoiding capital expenditure by renting usage from a third-party provider. They consume resources as a service and pay only for resources that they use. Many cloud-computing offerings employ the utility computing model, which is analogous to how traditional utility services (such as electricity) are consumed, whereas others bill on a subscription basis. Sharing "perishable and intangible" computing power among multiple tenants can improve utilization rates, as servers are not unnecessarily left idle (which can reduce costs significantly while increasing the speed of application development)


2 types of clouds:

* SaaS- Software as a service. Software that exists on the cloud. For example, Google documents allows users to create, edit, and share spreadsheets, text documents, and presentations similar to powerpoint. Or, Facebook. All of which is stored on the cloud.

* HaaS- Hardware as a service. Allows anyone to purchase space on a cloud in which they can place applications, games, and almost any software that usually sits on one’s desktop. Now, those applications will run in the cloud instead of taking up space on your computer. Examples: Amazon ec2, SaleForce.com