When you have a website hosting plan and you set up an e-mail address, you may consider the option to send out and receive emails for granted, however, this isn't always true. Sending emails isn't always part of the hosting plans that service providers will offer you and an SMTP service is necessary to be able to do that. The acronym stands for Simple Mail Transfer Protocol and this is the piece of software that allows you to send out e-mails. If you are using an e-mail application, it connects to the SMTP server. The latter then looks up 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 system data is exchanged, your SMTP server delivers the email to the remote IMAP or POP server and the email is finally delivered in the matching mailbox. An SMTP server is required if you work with some sort of contact form too, so in case you have a no charge hosting package, for instance, it is very likely that you will not be able to use such a form as many no charge website hosting companies don't allow outgoing e-mail messages.