In case you have a website hosting package and you create an email address, you may consider the option to send out and receive messages for granted, however, this isn't always the case. Sending e-mails is not always a part of the hosting plans that service providers have and an SMTP service is needed to be capable to do that. The acronym signifies Simple Mail Transfer Protocol and that is the set of scripts that allows you to send out e-mails. If you work with an email app, it creates a connection to the SMTP server. The latter then searches the DNS data of the domain, which is a part of the receiving address to find out what email server deals with its e-mails. After some system information is exchanged, your SMTP server delivers the message to the remote IMAP or POP server and the e-mail is finally delivered in the matching mailbox. An SMTP server is needed if you use some kind of contact form as well, so if you work with a free hosting package, as an example, it's probable that you will not be able to use such a form as many cost-free hosting providers don't allow outgoing e-mail messages.