What is Cloud Computing?

Cloud Computing is computing which is location indipendent, here in resourses software and data to the computers and other devices on demand is provided by shared servers. Cloud computing characteristics are derived from Automatic computing, Cliend-server model, Grid computing, Mainframe computer, utility computing, Service oriented computing. The key characteristic of the cloud computing is that computing is not in a specified, known place i.e, "in the cloud".  The main advantage of the cloud computing is
 that the cloud computing coustomers do not own the physical infrastructure instead they can avoid the capital expenditure on hardware, software and services when they pay the a third party provider for what they use. Other advantages of this model are immediate access to a wide range of applications, low management overhead, shared infrastructure and cost.