The difference between ado.net2 and ado.net4

Question

I studied ado.net 2005 

 

I am going to study  ado.net 2010

 

My question is , are there a big different between ado.net 2 and ado.net 4 

I know the LINQ is new , It wasn't in ado.net2 .

Appreciate your help and your support

Thank you