If you have a shared web hosting plan and you create an email address, you may take the option to send and receive emails for granted, but in fact, this is not always the case. Sending e-mail messages isn't always a part of the hosting plans that providers have and an SMTP service is necessary to be able to do that. The acronym stands for Simple Mail Transfer Protocol and this is the software application that permits you to send e-mails. If you are using an email app, it connects to the SMTP server. The latter then looks up the DNS data of the domain name, that is a part of the receiving address to find out what mail server deals with its emails. After system data is interchanged, your SMTP server provides the email to the remote IMAP or POP server and then the e-mail is finally delivered in the matching mailbox. An SMTP server is required if you are using some kind of contact page too, so if you have a cost-free hosting plan, for instance, it's probable that you will not be able to make use of such a form as many cost-free web hosting providers do not allow outgoing e-mails.