Problem with send mail

 I want to send mail from my Form, so i found the next code:
        Dim objMail As New MailMessage()
        objMail.From = "your_name@yourdomain.com"
        objMail.To = Request.Form("Email")
        objMail.Subject = Request.Form("Subject")
        objMail.Body = Request.Form("Message")
        objMail.BodyFormat = MailFormat.Text
        SmtpMail.SmtpServer = " smtp.your-server.com"
        SmtpMail.Send(objMail)
but i don't understand the next code:
1. "your_name@yourdomain.com" -- what is it my domain? Which e-mail?
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