SMTP, which stands for Simple Mail Transfer Protocol, is the software that permits you to send e-mail messages from your email addresses. Without this, you will not be able to employ e-mail apps or webmail. Every time you send an e-mail, your SMTP server connects to a DNS server to learn where the e-mails for the recipient domain are handled. Subsequently, it connects to the remote mail server and trades information. If the recipient mailbox is available, your server sends the message to the receiving POP/IMAP server and the latter delivers that e-mail to the precise mailbox in which the recipient can find it. If you want to be able to send e-mails, you should always ensure that the web hosting company offers the service with their packages. Even though you work with an online form that visitors use to contact you, you'll still require an active SMTP server for your hosting account for the web form to operate.