If you wish to send out e-mail messages through an e-mail address with your domain name, make sure that the company will provide you with usage of their SMTP server. The latter is the software system that allows emails to be sent. SMTP is an acronym for Simple Mail Transfer Protocol and it deals with all outgoing e-mails from apps, webmail and contact forms. When a message is sent, the SMTP server checks with all of the DNS servers throughout the world where the e-mails for the receiving domain name are taken care of and as soon as it obtains this info, it will connect into the remote POP/IMAP server to find out if the recipient mailbox exists. When it does, the SMTP server sends the message body while the receiving server sends it to the mailbox in which the recipient can open it and see it. Without an SMTP server on your end, you will not be able to mail out emails in any way.