When you've got a shared hosting plan and you create an e-mail address, you may consider the option to send out and receive emails for granted, but in fact, this is not always the case. Sending emails is not necessarily included in the web hosting packages that service providers feature and an SMTP service is necessary to be capable to do that. The abbreviation signifies Simple Mail Transfer Protocol and this is the piece of software that allows you to send e-mails. If you are using an email application, it creates a connection to the SMTP server. The latter then looks up the DNS data of the domain name, which is a part of the receiving address to find out which mail server deals with its e-mails. After some system information is swapped, your SMTP server delivers the e-mail to the remote IMAP or POP server and the e-mail is finally delivered in the related mailbox. An SMTP server is needed if you are using some sort of contact form as well, so if you use a free of charge hosting package, for instance, it is likely that you won't be able to use this type of form since many no charge website hosting providers don't allow outgoing emails.