SQL Server Configuration - Service Accounts
Use the Server Configuration page of the SQL Server Installation Wizard to assign login accounts to SQL Server services. The actual services configured on this page depend on the features you have selected to install.
You can assign the same login account to all SQL Server services, or you can configure each service account individually. You can also specify whether services start automatically, are started manually, or are disabled. Microsoft recommends that you configure service accounts individually to provide least privileges for each service, where SQL Server services are granted the minimum permissions they need to complete their tasks. For more information, see Setting Up Windows Service Accounts.