In case you have a shared web 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, that isn't always the case. Sending e-mail messages is not always included in the web hosting plans that providers feature and an SMTP service is necessary to be capable to do that. The abbreviation stands for Simple Mail Transfer Protocol and that is the software application that enables you to send out e-mails. If you are using an e-mail app, it creates a connection 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 handles its e-mails. After some system information is swapped, your SMTP server provides the message to the remote IMAP or POP server and then the email is finally delivered in the related mailbox. An SMTP server is necessary if you use some kind of contact page form as well, so in case you work with a free of charge hosting plan, as an example, it is very likely that you will not be able to use such a form as many free of charge web hosting companies do not allow outgoing email messages.