Cloud computing provides an on-line computing transparent resource to the user, since a user doesn’t notice almost no difference between working on her own computer or the cloud. Owned and managed by infrastructure providers, cloud computing entails advantages (concurrent access by many users, software updates hosted in the cloud, cost-efficiency or outsourced maintenance in the cloud) and disadvantages (loose of control, network Connection Dependency or security breaches ). On the other side, grid computing is a full network of computers and data working together so functioning as a supercomputer. Grid computing presents advantages such as shorter resolution of complex problems, the ease of organizational collaboration or a better use of existing hardware.