Evolution of Cloud Computing and Enabling Technologies

We present an overview of the history of forecasting software over the past 25 years, concentrating especially on the interaction between computing and technologies from mainframe computing to cloud computing. The cloud computing is latest one. For delivering the vision of various of computing models, this paper lightly explains the architecture, characteristics, advantages, applications and issues of various computing models like PC computing, internet computing etc and related technologies and also we summarized the current model cloud computing. Finally in this research paper, we described the need for convergence of competing IT paradigms to deliver our vision.