Cloud Computing - Part 1

I decided to start this Cloud Computing series on my blog as part of my research on the subject. This is Part 1 and I'm not really sure how many parts it's going to be finally but I hope to cover the essentials.
If you are new to the world of Cloud and would like to get a quick overview this is probably useful to you.
So what exactly is Cloud computing?
Cloud computing is processing on the web, think of it as your local community center where resources are shared e.g. you and your neighbors use the pool and pay the fee but you don't maintain it. These shared resources are provided to computers and devices and they are done on demand which I think is the most critical part of it. So if you don't need to use the resources someone else can use them, the sharing makes them more efficient.
Details of the underlying system are all abstracted from the end user. End users do not own the physical infrastructure of the system and pay only for resources used. This kind of abstraction ensures that businesses can focus on core business and allow the IT infrastructure to be managed by a third party.
The major Cloud service providers today are Google, Amazon and Salesforce. I will go into details of each of these vendors and their offerings in future posts.

Cloud computing basic architecture
The basic architecture of Cloud computing involves a front end and a back end. The front end is what is seen by the end user. The front end includes the end user's network and the applications used to access the cloud with a web browser or other interface. The back end of the cloud is comprised of various servers, data storage systems etc. The front end usually communicates with the back end using web services.

That's all I have in the way of introduction. In the next few parts I shall go into details of the different layers of cloud computing, deployment models and issues faced. I hope you continue to read...