Cloud computing security encompasses the policies, technologies, and controls designed to protect data, applications, and infrastructure hosted in cloud environments. In Australia, cloud computing security must align with the Australian Privacy Act, APRA CPS 234, and ACSC guidance on cloud risk management. It includes identity and access management (IAM), encryption, workload protection, configuration management, and continuous monitoring. Cloud computing security also addresses shared responsibility models between organisations and cloud service providers such as AWS, Microsoft Azure, and Google Cloud. Strong governance ensures sensitive information remains protected while maintaining regulatory compliance. Australian businesses adopting cloud-first strategies require robust cloud computing security frameworks to mitigate cyber threats, manage third-party risk, and maintain data sovereignty requirements.