Explanation
Service Cloud and Experience Cloud are two core Salesforce Clouds that Public Sector Solutions is based on.
Service Cloud is a Salesforce Cloud that can help public sector agencies to provide customer service and support, such as managing cases, creating knowledge articles, or using chatbots. Experience Cloud is a Salesforce Cloud that can help public sector agencies to create digital experience sites for external users, such as constituents, businesses, or employees. Public Sector Solutions is based on Service Cloud and Experience Cloud, and it provides additional features and components that are tailored for the delivery of government services. Reference:
https://help.salesforce.com/s/articleView?id=psc_admin_concept_psc_overview.htm&type=5&language=en_US