The concept of cloud computing has been introduced for several years. Many of us may be able to roughly imagine what it is, some of us may know how to describe it, but only a few do know how to implement it. Does NoSQL, MapReduce or Big Data equal to cloud computing? Can a service be said that it is cloud-based if it is using any of those tools? Many companies and groups have declared that their online services are cloud-based or they are using cloud computing, but are those all true? Except for the questions above, where should we start if we would like to establish a cloud-based service which is distributed, flexible, reliable, available, scalable and stable? This session intends to lead you through the gate of mysteries and head to the beautiful realm of cloud computing by using powerful tools, like Hazelcast. Welcome to journey with us to the core of cloud computing application!