When you've got a shared website hosting plan and you set up an e-mail address, you may take the option to send and receive messages for granted, but in fact, this is not always true. Sending emails isn't necessarily included in the website hosting plans that providers have and an SMTP service is needed to be able to do that. The abbreviation represents Simple Mail Transfer Protocol and this is the set of scripts that allows you to send out e-mails. If you are using an e-mail app, it connects to the SMTP server. The latter then looks up the DNS records of the domain, that is a part of the receiving address to find out what email server manages its email messages. After some system information is exchanged, your SMTP server provides the email to the remote IMAP or POP server and the e-mail is finally delivered in the matching mailbox. An SMTP server is required if you work with some kind of contact form also, so in case you use a no charge hosting package, as an example, it's probable that you won't be able to make use of such a form since many cost-free hosting service providers do not allow outgoing e-mails.