Modified the DataGrid reference link

Author: Backiaraj

README.md

@@ -1,2 +1,5 @@
 # How to define summary rows using AttachedProperty in wpf and uwp datagrid?
-This example illustrates how to define summary rows using AttachedProperty in wpf and uwp datagrid
+
+This example illustrates how to define summary rows using AttachedProperty in [WPF DataGrid](https://www.syncfusion.com/wpf-ui-controls/datagrid) (SfDataGrid).
+
+[WPF DataGrid](https://www.syncfusion.com/wpf-ui-controls/datagrid) (SfDataGrid) provides support to show the column summary. If the DataContext of SfDataGrid is ViewModel, you can bind [SummaryColumns](http://help.syncfusion.com/cr/cref_files/wpf/Syncfusion.SfGrid.WPF~Syncfusion.UI.Xaml.Grid.GridSummaryRow~SummaryColumns.html) to a property in ViewModel using the [AttachedProperty](https://docs.microsoft.com/en-us/dotnet/framework/wpf/advanced/attached-properties-overview) of type List<GridSummaryColumn>.