Cloud means separating the application from hardware and Operating system and this can be sharing and migrating to the other side.
Cloud Computing means storing and accessing data and program over the internet instead of your computer hard drive.
For Instance:Suppose Client is requesting a 4G Connection from Raichur and he is accessing a 2G connection. First he needs to access our portal, from that he can use our 4G connection by sitting in Raichur.
Why Cloud computing:
Hardware based virtualization: The complete simulation of actual hardware to allow software which typically consist of guest operating system to run unmodified.
Hypervisor is the software or firmware that create virtual machine on host or physical machine is called hypervisor or virtual manager.