A public cloud is a cloud computing model where the cloud infrastructure is owned and managed by a third-party cloud service provider, such as Amazon Web Services (AWS), Microsoft Azure, or Google Cloud. In a public cloud, the infrastructure and resources are shared among multiple organizations or users, who access and utilize the services over the internet. The cloud service provider is responsible for maintaining and managing the infrastructure, including hardware, software, and networking resources. Public clouds offer scalability, cost-efficiency, and ease of deployment since users can access and pay for the services on a pay-as-you-go basis.