In past few years, cloud computing spread all over the world as a new paradigm for giving some useful features like on demand infrastructure, SaaS and flexibility. As the name suggests cloud computing is a technology by which information exchange and software management done by virtual means, like in any programming language. Now-a-days, for complex and large data storage a powerful network architecture is used which is termed as cloud computing. Cloud computing is independent of location customers can use resources from any device and any time when they needed, they can use free or pay basis. In this paper, the authors are describe concept and architecture of cloud computing.