The purpose of the cloud in cloud computing is to provide on-demand access to computing resources, such as servers, storage, and applications, over the internet. This model allows users to scale resources up or down based on their needs, optimizing costs and improving accessibility. By leveraging cloud services, organizations can avoid the complexities associated with managing physical infrastructure and benefit from features like automatic updates, data backup, and enhanced collaboration. Overall, the cloud enhances flexibility and innovation in business operations.