In case you have a shared website hosting package and you set up an e-mail address, you may consider the option to send and receive emails for granted, but in fact, that isn't always the case. Sending email messages isn't always part of the web hosting plans that providers offer and an SMTP service is required to be capable to do that. The acronym stands for Simple Mail Transfer Protocol and this is the set of scripts that permits you to send out e-mail messages. If you are using an e-mail application, it creates a connection to the SMTP server. The latter then requests the DNS data of the domain, that is a part of the receiving address to find out which email server manages its e-mails. After some system information is interchanged, your SMTP server delivers the email to the remote IMAP or POP server and the e-mail is finally delivered in the related mailbox. An SMTP server is necessary if you use some kind of contact form as well, so if you work with a free hosting package, for example, it is very likely that you will not have the ability to use this type of form as most cost-free hosting companies don't allow outgoing email messages.