When you've got a shared hosting plan and you set up an e-mail address, you might consider the option to send out and receive messages for granted, but in fact, that isn't always true. Sending emails isn't necessarily included in the hosting packages that companies will offer you and an SMTP service is required to be capable to do that. The abbreviation signifies Simple Mail Transfer Protocol and this is the piece of software that enables you to send out e-mails. If you work with an email application, it creates a connection 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 which mail server deals with its emails. After system data is swapped, your SMTP server delivers the email to the remote IMAP or POP server and then the email is finally delivered in the related mailbox. An SMTP server is needed if you are using some kind of contact form also, so in case you work with a free hosting package, for example, it is likely that you will not have the ability to use such a form since many free web hosting service providers don't allow outgoing e-mail messages.