SMTP, which stands for Simple Mail Transfer Protocol, is the software that allows you to send out e-mail messages from your email addresses. Without this, you won't be able to use email applications or webmail. Every time you send a message, your SMTP server creates a connection to a DNS server to determine exactly where emails for the recipient domain name are taken care of. Following that, it creates a connection to the remote email server and exchanges information. If the recipient mail box exists, your server transmits the email to the receiving POP/IMAP server and the latter delivers that e-mail to the specific mailbox in which the receiver can access it. If you'd like to be able to send e-mails, it is recommended to make certain that the web hosting company offers the service with their plans. Even though you work with an online form that visitors use to contact you, you still require an active SMTP server for your hosting account for the web form to function.