When you have a hosting plan and you set up an e-mail address, you might take the option to send out and receive emails for granted, however, this is not always the case. Sending e-mails isn't necessarily included in the hosting plans that companies will offer you and an SMTP service is required to be able to do that. The abbreviation signifies Simple Mail Transfer Protocol and this is the software application that allows you to send emails. If you use an email application, it connects to the SMTP server. The latter then requests the DNS records of the domain, which is a part of the receiving address to find out what email server manages its e-mails. After some system data is swapped, your SMTP server provides the message to the remote IMAP or POP server and the e-mail is finally delivered in the matching mailbox. An SMTP server is required if you use some sort of contact page form as well, so if you use a free of charge hosting plan, for instance, it's probable that you will not be able to use such a form as most cost-free website hosting providers don't allow outgoing email messages.