see this link on server.transfer method
http://www.mindstick.com/Blog/38/Server%20Transfer%20how%20use%20it

Server.Transfer is used as response.redirect but it give the better and fast result as redirect.
we use server.transfer in our application as
step 1:
we take one textbox and one button on home page and write the code on button click as
Server.Transfer("Default.aspx");
step 2;
we get the value of textbox of home page by
write this code on default.aspx
 Page page1 = this.PreviousPage;
        TextBox t = (TextBox)page1.FindControl("TextBox1");
        Response.Write(t.Text);