IaaS is abbreviated form of the Infrastructure as a service. This term is widely used in the cloud computing. If you haven’t heard about it then you must hurry and do some researches in it. As we move on to the cloud computing the Iaas has more and more use. It provides a infrastructure in the cloud. Many vendors provides the infrastructure and it is pay per use. i.e. you have to pay for the infrastructure that you use. Sometimes all you need is high configuration hardware and sometimes just only little is enough in the corporation. Such can be easily implemented in IaaS within the cloud. And all you have to pay is what you use. I guess in future every corporation will desire to choose the IaaS platform of the cloud for their hardware infrastructure and it is really going huge these days. The main thing that we need to understand about the IaaS of cloud is that the vendors manages the lower level of the stack. Currently only few vendors provides the operating system and it needs to be managed by user. Sometimes the user needs to install the operating system too. But the benefit of the IaaS over the cloud is that it does not require any physical servers. It works with the virtual machines in which the servers or the operating system can be installed.