Cloud Computing is a relatively new term that conveys the use of information technology services and resources that are provided on a service basis. According to a 2008 IEEE paper, “Cloud Computing is a paradigm in which information is permanently stored in servers on the internet and cached temporarily on clients that include desktops, entertainment centers, table computers, notebooks, wall computers, hand-helds, sensors, monitors, etc.”
The name comes from the use of a cloud-shaped symbol as an abstraction for the complex infrastructure it contains in system diagrams.
In the current (but still evolving!) model of cloud computing, the cloud computing infrastructure consists of services that are offered up and delivered through data centers that can be accessed from anywhere in the world.
In cloud computing models, customers do not own the infrastructure they are using, they basically rent it, or pay as they use it. The loss of control is seen as a negative, but it is generally out-weighed by several positives. One of the major selling points of cloud computing is lower costs. Companies will have lower technology-based capital expenditures, which should enable companies to focus their money on delivering the goods and services that they specialize in.
There will be more device and location independence, enabling users to access systems no matter where they are located or what kind of device they are using. The sharing of costs and resources amongst so many users will also allow for efficiencies and cost savings around things like performance, load balancing, and even locations (locating data centers and infrastructure in areas with lower real estate costs, for example).
Cloud computing is also thought to affect reliability and scalability in positive ways. One of the major topics in information technology today is data security. In a cloud infrastructure, security typically improves overall, although there are concerns about the loss of control over some sensitive data. Finally, cloud computing results in improved resource utilization, which is good for the sustainability movement.