If you want to send emails using an e-mail address with your very own domain, you have to make sure that the company will give you usage of their SMTP server. The aforementioned is the software system enabling e-mail messages to be sent. SMTP is an abbreviation for Simple Mail Transfer Protocol and it handles all outgoing email messages from apps, webmail and contact forms. Every time a message is sent out, the SMTP server checks with all of the DNS servers globally where the e-mails for the receiving domain are taken care of and when it acquires this info, it creates a connection into the remote POP/IMAP server to see if the recipient mail box is out there. If it does, the SMTP server sends the message body and then the receiving server sends it to the mail box where the recipient can open it and read it. Without an SMTP server on your server, you won't be able to send emails at all.