If you have a shared hosting plan and you set up an email address, you may consider the option to send and receive messages for granted, however, this isn't always the case. Sending e-mails is not necessarily included in the website hosting packages that companies offer and an SMTP service is required to be able to do that. The abbreviation represents Simple Mail Transfer Protocol and this is the set of scripts that permits you to send out emails. If you are using an e-mail application, it connects to the SMTP server. The latter then requests the DNS records of the domain, that is a part of the receiving address to find out which mail server manages its e-mails. After system information is interchanged, your SMTP server provides the message to the remote IMAP or POP server and the e-mail is finally delivered in the corresponding mailbox. An SMTP server is required if you are using some kind of contact form also, so if you have a free of charge hosting plan, for example, it is very likely that you won't have the ability to use such a form as most free of charge website hosting providers do not allow outgoing emails.