Simply put, cloud computing is the delivery of computing services—including servers, storage, databases, networking, software, analytics, and intelligence—over the Internet.
Cloud computing is a paradigm shift in which computing is moved away from personal computers and even the individual enterprise application server to a ‘cloud’ of computers. A cloud is a virtualized server pool which can provide the different computing resources of their clients. Users of this system need only be concerned with the computing service being asked for.
The data and the services provided reside in massively scalable data centers and can be ubiquitously accessed from any connected device all over the world. Cloud computing is the style of computing where massively scaled IT related capabilities are provided as a service across the internet to multiple external customers.