Developer's Guide (Reporting Services)
SQL Server Reporting Services offers several programming interfaces that you can leverage in your own applications. You can use the existing features and capabilities of Reporting Services to build custom reporting and management tools into Web sites and Windows applications, or you can extend the Reporting Services platform.
Extending the Reporting Services platform includes creating new components and resources that can be used for data access, report delivery and more. You can market these components and resources to companies that are using Reporting Services in their organization.