The document discusses various methods for integrating ServiceNow with external systems and populating the configuration management database (CMDB). It describes integration use cases like authentication, bulk data import/export, and transactional data exchange. Specific integration methods covered include the mid server, import sets, transform maps, REST API explorer, REST messages, processors, and web services. The document provides guidance on best practices for integrations and details on integration interfaces like email, JDBC, JSON, SOAP, REST, and data export.