Please refer to the following URL to know the differences between Typed DataSet and Untyped DataSet,http://onlydifferencefaqs.blogspot.in/2012/08/adonet-difference-faqs-2.html

http://www.dotnetquestion.info/dot_net/ado_net.php

typed dataset we can assign particular datatype and field name

Typed datasets are more self documenting and easier to work with at design
time (overall).
MyTypedDataSet.MyDoctor.FirstName = "Fred"
vs.
MyUntypedDataSet.Tables("Doctors").Row(0).Item(1)= "Fred"