Response.Redirect("http://yahoo.com");

You can also use PostbackUrl property associated with  
button control in ASP.NET,
such as : <asp:button id = "b1" PostBackUrl = "www.sify.com"
            runat = "server" Text = "redirect"/>

you can use the link button control in that control there is a property c/d NavigateUrl in which u specify either the URL of any site or any page of the application...

Hi Anjani, there is a mistake in answer is that the link button control doesn't contain the NavigateUrl property but we do this task by doing this in the linkbutton control source view is:

   <asp:LinkButton ID="lnkbtn" runat="server"      OnClick="lnkbtn_Click" OnCommand="link"><a href="http://www.google.com">Link</a></asp:LinkButton>
  </div>

responce.redirect(http//:gmail.com)

Response.Redirect("link name");

http://www.interview-questions.maxmice.com

There is a mistake in answer is that the link button 
control doesn't contain the NavigateUrl property but we do 
this task by doing this in the linkbutton control source 
view is:

   <asp:LinkButton ID="lnkbtn" runat="server"      
OnClick="lnkbtn_Click"><a 
href="http://www.google.com">Link</a></asp:LinkButton>
  </div>

The OnCommand="link" is not needed.

<asp:LinkButton ID="lnkbtn" OnClick="lnkbtn_Click" 
runat="server" >
        <a href="http://www.google.com">Link</a>
    </asp:LinkButton>