When you've got a shared hosting plan and you set up an email address, you may take the option to send out and receive messages for granted, however, that isn't always the case. Sending e-mail messages is not necessarily part of the hosting plans that service providers have and an SMTP service is needed to be capable to do that. The abbreviation means Simple Mail Transfer Protocol and this is the software application that permits you to send e-mails. If you use an email app, it creates a connection to the SMTP server. The latter then queries the DNS data of the domain, that is a part of the receiving address to find out what email server manages its emails. After system information is exchanged, your SMTP server delivers the message to the remote IMAP or POP server and then the e-mail is finally delivered in the matching mailbox. An SMTP server is necessary if you use some kind of contact page too, so in case you use a cost-free hosting plan, for example, it is likely that you will not have the ability to use this type of form since many cost-free hosting companies don't allow outgoing e-mails.