DataGrid provides a way to edit the data and SET the properties to create a good USER interface.
DataGrid provides a way to create an application that provides interactivity by using the set or unset of the methods LIKE CanUserAddRows, CanUserDeleteRows, CanUserReorderColumns, etc.
To edit look for the properties that starts with CAN and change it according to the REQUIREMENTS.
Adding or modifying of a row or data effects the collection of the Items that is assigned to the ItemsSource.