SMTP, which is short for Simple Mail Transfer Protocol, is the software that enables you to send e-mails from your email addresses. Without it, you will not be able to employ e-mail applications or webmail. Once you send an e-mail, your SMTP server creates a connection to a DNS server to find out where the e-mails for the recipient domain are handled. Subsequently, it connects to the remote mail server and trades information. In case the recipient mail box is accessible, your server transmits the message to the receiving POP/IMAP server and the latter delivers that email to the precise mailbox where the receiver can find it. If you'd like to be able to send emails, you should always make certain that the web hosting company offers the service with their packages. Even if you make use of online form that website visitors use to make contact with you, you'll still need an active SMTP server for your hosting account for the web form to function.