When you've got a website hosting package and you create an e-mail address, you may consider the option to send out and receive messages for granted, but in fact, this is not always the case. Sending email messages isn't always part of the hosting packages that service providers offer 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 emails. If you are using an e-mail app, it connects to the SMTP server. The latter then queries the DNS data of the domain name, that is a part of the receiving address to find out what mail server manages its emails. After some system information is exchanged, your SMTP server delivers 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 also, so if you have a cost-free hosting package, as an example, it is likely that you will not be able to make use of this type of form as many cost-free web hosting service providers do not allow outgoing e-mail messages.