Through the 1990s to 2012 the internet changed the world of computing drastically. It started its journey with parallel computing after it advanced to distributed computing and further to grid computing. And in present scenario it creates a new world which is pronounced as a Cloud Computing [1]. These all three terms have different meanings. Cloud computing is based on backward computing schemes like cluster computing, distributed computing, grid computing and utility computing. The basic

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... t of cloud computing is virtualization. It provides virtual hardware and software resources to various requesting programs. This paper gives a detailed description about cluster computing, grid computing and cloud computing and gives an insight of some implementations of the same. We try to list the inspirations for the advent of all these technologies. We also account for some present scenario faults of grid computing and also discuss new cloud computing projects which are being managed by the Government of India for learning. The paper also reviews the existing work and covers (analytically), to some extent, some innovative ideas that can be implemented.