Abstract: Cloud computing is ondemand, pay per use service which is for users convenience and here the user has not pay for maintenance cost. It is a computing platform for the next generation. Because of it is new technology, it has both advantages and disadvantages. Cloud refers to a scalable networks of computers that work together like internet. Cloud deployment models are: SaaS, PaaS, IaaS. It helps in many ways the IT industry and also improve efficiency.