Typed DataSet
1.It provides additional methods, properties and events and thus it makes it easier to use.
2.They have .xsd file (Xml Schema definition) file associated with them and do error checking regarding their schema at design time using the .xsd definitions.
3.We will get advantage of intelliSense in VS. NET.
4.Performance is slower in case of strongly typed dataset.
5.In complex environment, strongly typed dataset's are difficult to administer.
6.Typed DataSets use explicit names and DataTypes for their members.
Example: northwindDataSet.Products.ProductNameColumn.Caption = "pnames";
Untyped DataSet
1.It is not as easy to use as strongly typed dataset.
2.They do not do error checking at the design time as they are filled at run time when the code executes.
3.We cannot get an advantage of intelliSense.
4.Performance is faster in case of Untyped dataset.
5.Untyped datasets are easy to administer.
6.UnTyped DataSets use table and column collections for their members.
Example: ds.Tables["emp"].Columns["eno"].ReadOnly=true;