Cloud computing is the phrase used to describe different scenarios in which computing resource is delivered as a service over a network connection (usually, this is the internet).
The Cloud Computing concept is the vast computing resources which can be located somewhere instead within your computer room and you can connect and use them as per the need, which means it allows companies to use latest and appropriate technology as a service, be it Software as a Service (SaaS) or Infrastructure as a Service (IaaS), with the flexibility to pay-per-use business models by moving to IT as a subscription so that you get to pay for what you use, when you use it.