What is cloud computing? We hear this term everywhere, but what does it really mean? We have all used the cloud knowingly or unknowingly. If you use Gmail, Hotmail, or any other popular e-mail service, you have used the cloud. Simply put, cloud computing is a set of pooled computing resources and services delivered over the Web.

Client computing is not a new concept in the computer industry. Those of you who have been in the IT business for a decade or two will remember that the first type of client-server applications were the mainframe and terminal applications. At that time, storage and CPU was very expensive, and the mainframe pooled both types of resources and served them to thin-client terminals.

With the advent of the PC revolution, which brought mass storage and cheap CPUs to the average corporate desktop, the file server gained popularity as a way to enable document sharing and archiving. True to its name, the file server served storage resources to...