When you have a shared hosting account and you set up an e-mail address, you may consider the option to send and receive messages for granted, but in fact, that isn't always the case. Sending e-mail messages isn't always a part of the web hosting plans that providers will offer you and an SMTP service is needed to be able to do that. The abbreviation signifies Simple Mail Transfer Protocol and that is the piece of software that allows you to send out e-mails. If you use an email app, it connects to the SMTP server. The latter then searches the DNS records of the domain name, that is a part of the receiving address to find out what mail server manages its email messages. After system information is exchanged, your SMTP server provides the message to the remote IMAP or POP server and the email is finally delivered in the related mailbox. An SMTP server is required if you are using some sort of contact form too, so if you work with a no charge hosting plan, as an example, it's probable that you won't have the ability to make use of such a form as many free hosting service providers don't allow outgoing e-mail messages.