Technology advances, and with it, new terms build up. Grid computing has been shifted to “Cloud Computing”. As the name suggests the data is somewhere in the clouds simply because large groups of servers that often use low-cost consumer PC technology are networked together, with specialized connections to spread data-processing chores across them.
You don’t know where the server located is and where is the data amongst multiple servers but it is ensured that you have created repository of information which will stay lifelong irrespective of common problems of losing data- computer crashes; file lost or damaged.
All you need to implement cloud computing is: servers, nodes to connect to server, a controlling server to handle other servers, applications to be loaded on the cloud,
fast internet connections and an open source software required for binding the clusters and provide virtualization.
One of the best examples of implementing the Cloud is Google Apps, which not only implements so called virtualization by allowing companies to run multiple applications on a single server computer but also makes it as an open source by collaborating the data of multiple companies under a single unit. Software as a Service (SaaS, typically pronounced 'sass') is a model of software deployment where an application is hosted as a service provided to customers across the Internet. By eliminating the need to install and run the application on the customer's own computer, SaaS alleviates the customer's burden of software maintenance, ongoing operation, and support. Cloud computing easily manages Saas by reducing the overhead involved in buying the software simply by offering “on demand pricing”.
Since the simple storage service is provided by the vendor, there are lot of risks being involved in the technology
