Cloud computing providers offer active and convenient accessibility to clients, such as on-demand and pay-per-use services. Cloud computing users save IT cost since they only pay for what they used; they do not need to invest in hardware, software, networking, and hiring IT staff inside organizations. Security service is handled by cloud computing providers, however, the user organizations are the major concern of security breach. Another important benefit of moving to the cloud is the scalability and flexibility of IT that are offered by cloud computing vendors. Cloud computing users can enjoy the suppleness of workload changes, especially handling growing business transactions during the hot season. Users moving to cloud computing just are like outsourcing their IT operations to the vendors. For this reason, users do not need to handle IT management tasks in the organization. Another benefit of moving to the cloud is the enhancement of mobility, that is, clients can have access to the software at any place they go to, as long as the Internet access is feasible.