In this article, you got a good start working with data and data binding in ASP.NET. Specifically, here's what you accomplished:
You created a Connection object that contains information on the location and type of data.
You created a DataAdapter object that handles retrieving the data using the Connection object.
You generated a typed DataSet, a class that handles providing the data to data-bound controls.
You bound a DataGrid control to the typed DataSet, displaying data on the page.
You added a bound DropDownList control and filtered the data in the DataGrid based on the selection in the drop-down list.