Look into following code block,
DataTable _table = new DataTable();
//1) Why I need to Convert DataRow again into DataRow by Casting ?
List<DataRow> _rows = _table.Rows.Cast<DataRow>().Select(a => a).ToList();
//2) Why this is not valid?
List<DataRow> _rows = _table.Rows.Select(a => a).ToList();
In first case why I need to convert DataRow again into DataRow? and Why second case not valid?