Cloud Computing tutorial for beginners

Is there a good cloud computing tutorial for beginners, I searched and found lot of marking articles, but not finding good technical article for understanding Cloud Computing Technology.
PaaS: Platform as a service is when the provider gives a computing platform. This includes all the basics of computing like an OS, database, web server and so on.

SaaS: Software as a service is when the provider gives software for use to its users. This software resides on the remote server and is available through the internet for usage.

IaaS: Infrastructure as a service is when users get resources for usage.

What is Cloud Computing? You can also find an architectural diagram of Cloud Computing technology there.
IIT-B has a number of research papers on cloud computing, you can find them all here: IIT-B Research papers on Cloud Computing
These links were helpful thanks team
Here is a collection of Cloud Computing technical articles at Collegelib: Cloud articles. From Cloud computing architecture diagram to Cloud operating systems