SMTP, which is short for Simple Mail Transfer Protocol, is the software that permits you to send e-mail messages from your email addresses. Without it, you will not be able to employ email apps or webmail. Once you send an email, your SMTP server creates a connection to a DNS server to find out exactly where emails for the recipient domain are managed. After that, it connects to the remote email server and trades information. If the recipient mail box is accessible, your server sends the message to the receiving POP/IMAP server and the latter delivers that email to the particular mailbox in which the recipient can find it. If you would like to send e-mails, you should always ensure that the web hosting company provides the service with their packages. Even though you use an online form that visitors use to get hold of you, you still need an active SMTP server for your hosting account for the form to function.