What is cloud computing?

There are lot of buzz around cloud computing. Almost all big and small companies are talking about cloud computing.
                Cloud computing is service of IT (Information Technology) infrastructure and managed sharing of IT resources.
In network diagram(as shown below) internet icon is displayed like cloud. This typically means an area of the diagram or solution that is some else’s concern. The word Cloud in cloud computing is derived from this diagram.  


To understand more about cloud computing we take a car rent example. User rents a car when he needs. User never worries about car maintenance, insurance or other car expenses, he pays for car rent service only.
 Similar to car rent, cloud computing provides service over the internet.  The beauty of cloud computing is that other company hosts your application. That means they handle the cost of server, maintenance of server and manage software update as per user’s requirement. User pays less for service only. User can increase or decrease service of server as per application requirement. Like user need more server instances in November and December month due to high volume of traffic. So user can demand more server instances for those months only. There is no need to keep all server instances for the whole year. In this way the company saves a lot of money in maintenance of server.
    In summary, Cloud computing provide rapid access to computing at a lower cost of ownership, enabling companies to perform operation that may have previously been unaffordable or impractical.