In the SaaS (Software as a Service) model, the service provider manages the infrastructure, platforms, and software applications, including maintenance tasks such as application patching. Users access the applications over the internet, and the provider is responsible for ensuring the software is up to date, secure, and performing optimally. This model contrasts with IaaS (Infrastructure as a Service) and PaaS (Platform as a Service), where the customer has more control and responsibility over the environment and may need to manage patching for applications they develop or install.