If you have a cloud hosting account and you create an e-mail address, you may take the option to send out and receive emails for granted, but in fact, that isn't always the case. Sending emails isn't always a part of the hosting plans that companies will offer you and an SMTP service is needed to be able to do that. The acronym stands for Simple Mail Transfer Protocol and that is the piece of software that enables you to send email messages. If you are using an email app, it creates a connection to the SMTP server. The latter then searches the DNS data of the domain, that is a part of the receiving address to find out which mail server manages its email messages. After some system information is swapped, your SMTP server delivers the e-mail 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 kind of contact form as well, so if you use a free hosting plan, as an example, it is likely that you won't be able to use such a form since many no charge website hosting service providers don't allow outgoing e-mail messages.