Public clouds are shared environments managed by third-party providers, allowing multiple clients to utilize resources on a pay-as-you-go basis. In contrast, private clouds are dedicated resources used exclusively by a single organization, offering enhanced security and customization. Public clouds typically have lower costs due to shared resources but may pose risks regarding data privacy and compliance. Conversely, private clouds ensure greater control and security but often incur higher operational costs. The choice between public and private clouds depends on factors such as security needs, compliance requirements, and budget constraints.