Abstract: Cloud computing is rapidly growing and is gaining popularity across the world because of its numerous features. Cloud computing has evolved from simple networking applications. Its functioning is however based on models of cluster and grid computing. Cluster, Cloud and Grid Computing are practices of distributed and local computing. Cluster consists of computers connected over a LAN, whereas cloud and grid are geographically distributed on a wider scale. This paper strives to compare, contrast and analyze cloud computing with grid computing and cluster computing from various aspects and in conclusion give an understanding of their crucial characteristics.

Keywords: cloud classification, cloud computing, cluster computing, fabric grid, grid computing, high availability cluster.