SMTP, which is an acronym for Simple Mail Transfer Protocol, is the software that allows you to send out messages from your email addresses. Without this, you won't be able to employ email applications or webmail. Once you send an email, your SMTP server creates a connection to a DNS server to discover exactly where emails for the recipient domain are handled. Following that, it creates a connection to the remote mail server and exchanges information. In case the recipient mailbox exists, your server sends the e-mail to the receiving POP/IMAP server and the latter brings that email to the precise mailbox in which the receiver can get it. If you would like to be able to send emails, you should always make certain that the website hosting company provides the service with their plans. Even when you make use of online form that site visitors use to get hold of you, you will still require an active SMTP server for your hosting account for the web form to operate.