Cloud computing has leaped ahead as one of the biggest technological advances of the present time. In cloud, users can upload or retrieve their desired data from anywhere in the world at anytime, making this the most important and primary function in cloud computing technology. While this technology reduces the geographical barriers and improves the scalability in the way we compute, keeping data in a Cloud Data Center (CDC) faces numerous challenges from unauthorized users and hackers within the system. Creating proper Service Level Agreements (SLA) and providing high-end storage security is the biggest barrier being developed for better Quality of Service (QoS) and implementation of a safer cloud computing environment for the Cloud Service Users (CSU) as well as for the Cloud Service Providers (CSP). Therefore, cloud applications need to have increased QoS and effective security measures and policies set in place to provide better services and to decline unauthorized access. The purpose of this chapter is to examine the cloud computing technology behind innovative business approaches and establishing SLA in cloud computing applications. This chapter provides a clear understanding of different cloud computing security challenges, risks, attacks, and solutions that exist in the present heterogeneous cloud computing environment. Storage security, different cloud infrastructures, the many advantages, and limitations are also discussed.