In case you have a shared website hosting account and you set up an email address, you may consider the option to send out and receive messages for granted, but in fact, this isn't always true. Sending e-mail messages isn't necessarily part of the web hosting plans that companies will offer you and an SMTP service is required to be capable to do that. The acronym represents Simple Mail Transfer Protocol and that is the software application that allows you to send e-mail messages. If you use an email app, it creates a connection to the SMTP server. The latter then looks up the DNS records of the domain name, that is a part of the receiving address to find out what email server deals with its emails. After system data is interchanged, your SMTP server provides the e-mail to the remote IMAP or POP server and the e-mail is finally delivered in the corresponding mailbox. An SMTP server is necessary if you use some kind of contact page form as well, so if you have a free of charge hosting package, for example, it is likely that you won't have the ability to use such a form as many cost-free hosting service providers do not allow outgoing emails.