Cloud Computing is a general term that refers to the use of a collection of computers, or servers, as a single unit that automatically distributes data and/or tasks amongst the “cloud” of computers. This has recently gained notoriety because of companies like Google and Apple who are currently exploring the offering of Cloud Services to their users. Cloud Computing should not be confused with “distributed computing” which refers to a collection of computers that share computational cycles to achieve a single goal (e.g. Folding@Home).

Cloud Computing is actually just a conceptual representation of a network architecture that allows users to access the “cloud” to run applications and/or store data. The “cloud” of computers act like a single computer, running the same operating system and sharing storage space. The architecture is ultimately invisible to the end user, but the benefit is a large number of users accessing the same storage space or software at the same time. One example is Google's App Engine, which allows software developers all over the world to develop applications in the same environment (resources such as software libraries) as Google employees.

The concept of Cloud Services is only slightly more specific. A good example of this is the collection of applications that Google provides called Google Apps which include email, word processing, spreadsheets, and calendaring. Google's Cloud Services allow a user to save files on Google's servers and then access them via an email account, a word processor or a spreadsheet application. Apple recently announced at their WWDC, their intention to start offering Cloud Services via their MobileMe service. This service allows users to access the same data from a variety of devices or locations. Specifically, they are offering “push” email, contacts and calendar. This allows changes made to your data to be uploaded and then distributed to all of your devices, whether that device is a phone, a PC or a Mac. They are also now offering a suite of web based applications that will allow users to access the same email, calendar, address book or files that they keep on their computer or phone from just about any computer connected to the internet.

Of course, security is likely to be a major concern for many people. Google has made the comparison between your files and your money. Not too many people keep large amounts of cash hidden in their homes. In the same way, they are suggesting that you can now keep your data, email, contacts and schedules on their servers. Consider that banks are able to afford much greater security than most people are, to protect their assets. In the same way, Google can afford and offer much better hardware and software to protect your data and keep it secure because they are offering these cloud services to a huge number of people.