“Cloud” Computing – a Relatively Recent Term, Builds on Decades of Research In Virtualization, Distributed Computing, Utility Computing, and More Recently Networking, Web and Software Services. It Implies a Service Oriented Architecture, Reduced Information Technology Overhead For the End-User, Great Flexibility, Reduced Total Cost of Ownership, On-Demand Services and Many Other Things. This Paper Discusses the Concept of “Cloud” Computing, some of the Issues It Tries to Address, Related Research Topics, and a “Cloud” Implementation Available Today.