SMTP, which stands for Simple Mail Transfer Protocol, is the software that enables you to send out emails from your email addresses. Without this, you will not be able to employ e-mail applications or webmail. Whenever you send a message, your SMTP server connects to a DNS server to learn exactly where e-mails for the recipient domain name are taken care of. Then, it connects to the remote email server and exchanges details. If the recipient mailbox is present, your server transmits the message to the receiving POP/IMAP server and the latter brings that email to the precise mailbox where the receiver can see it. If you would like to be able to send e-mails, you should always ensure that the web hosting company has the service with their packages. Even though you make use of online form that visitors use to make contact with you, you still require an active SMTP server for your hosting account for the web form to function.