In case you have a cloud hosting package and you set up an e-mail address, you may take the option to send out and receive emails for granted, however, this is not always true. Sending e-mails is not always a part of the web hosting plans that service providers have and an SMTP service is necessary to be able to do that. The abbreviation signifies Simple Mail Transfer Protocol and this is the set of scripts that allows you to send out emails. If you are using an email app, it connects to the SMTP server. The latter then looks up the DNS records of the domain, which is a part of the receiving address to find out what email server deals with its emails. After system information is swapped, your SMTP server delivers the e-mail to the remote IMAP or POP server and then the e-mail is finally delivered in the related mailbox. An SMTP server is necessary if you use some sort of contact page as well, so in case you work with a no charge hosting package, for instance, it is very likely that you won't have the ability to make use of such a form since many cost-free website hosting providers don't allow outgoing e-mails.