Science and Education Publishing American Journal of Software Engineering 2 1 2014 03 18 Comparison of Cloud and Grid Computing 8 12 EN J. Pourqasem S. Karimi S.A. Edalatpanah Department of Applied Mathematics, Lahijan Branch, Islamic Azad University, Lahijan, Iran AJSE2014212 10.12691/ajse-2-1-2 2013 10 27 2014 03 17 2014 03 18 Cloud computing is emerged from internet technology that is distinguished from previous generation of distributed systems i.e. Grid Computing. Grid Computing and Cloud Computing have similarity and difference in basic components. In this paper we present a comparison of Grid Computing and Cloud Computing between principles of them. Furthermore, this paper gives insights into the essential characteristics of both.