how to send email using C#.net

MailMessage msg = new MailMessage();
msg.From = new MailAddress("from@gmail.com", "Display name");
msg.Subject = "Hello mail!";
msg.Body ="This is my email";
// Set more properties if you like.

SmtpClient client = new SmtpClient();
// Set client properties. Authentication, smtp server etc. or use app.config (see below)
client.Send(msg);

<system.net>
    <mailsettings>
      <smtp from="from@gmail.com">
        <network host="smtp.mail.com" port="587" username="from@mail.com" password="***" />
      </smtp>
    </mailsettings>
  </system.net>