difference between DataContract and DataContractSerializer

Question

difference between   DataContract and  DataContractSerializer !
when and how to choose each one !

Answer 1

first problem solved i used the following code : protected void FileSaveAs_Click(object sender, EventArgs e) { Object o = null; AxWebBrowser1.ExecWB(SHDocVw.OLECMDID.OLECMDID_SAVEAS, SHDocVw.OLECMDEXECOPT.OLECMDEXECOPT_PROMPTUSER, ref o, ref o); } but i still have the open htm file problem, any ideas ? Thanks