What is DTS / SSIS in SQL Server?

SSIS = SQL Server Integration Services. From Microsoft:

Microsoft Integration Services is a platform for building data integration and data transformation solutions at the enterprise level. You use Integration Services to solve complex business problems by copying or downloading files, sending e-mails in response to events, updating data stores, cleaning and data mining, and managing SQL Server objects and data. Packages can work alone or in conjunction with other packages to meet complex business needs. Integration Services can extract and transform data from a wide variety of sources, such as XML data files, flat files, and relational data sources, and then load the data to one or more destinations.Integration Services includes a rich set of built-in tasks and transformations; tools for creating packages; and the Integration Services service for starting and managing packages. You can use the Integration Services graphical tools to create solutions without writing a single line of code; or you can program the extensive Integration Services object model to programmatically create packages and create custom code tasks and other package objects.or you can program the extensive Integration Services object model to programmatically create packages and create custom code tasks and other package objects.or you can program the extensive Integration Services object model to programmatically create packages and create custom code tasks and other package objects.

http://msdn.microsoft.com/en-us/library/ms141026.aspx

It's actually really cool. Oracle also has a pretty cool business intelligence editor for their dbms.