In case you have a web hosting package and you create an email address, you might consider the option to send and receive emails for granted, but in fact, this is not always true. Sending emails isn't necessarily included in the hosting packages that service providers offer and an SMTP service is required to be able to do that. The abbreviation means Simple Mail Transfer Protocol and that is the piece of software that enables you to send out email messages. If you are using an e-mail app, it connects to the SMTP server. The latter then queries the DNS records of the domain name, which is a part of the receiving address to find out which mail server deals with its e-mails. 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 corresponding mailbox. An SMTP server is required if you use some sort of contact page as well, so in case you have a free of charge hosting plan, as an example, it's probable that you won't have the ability to use this type of form since many free of charge website hosting service providers don't allow outgoing e-mail messages.