SMTP, which is short for Simple Mail Transfer Protocol, is the software that enables you to send out e-mail messages from your email addresses. Without it, you won't be able to employ e-mail apps or webmail. Whenever you send a message, your SMTP server creates a connection to a DNS server to determine exactly where emails for the recipient domain are handled. Following that, it creates a connection to the remote email server and trades details. When the recipient mailbox exists, your server transmits the message to the receiving POP/IMAP server and the latter delivers that email to the precise mailbox where the recipient can get it. If you'd like to send emails, it is recommended to make sure that the website hosting company has the service with their packages. Even if you use an online form that visitors use to make contact with you, you will still need an active SMTP server for your hosting account for the form to work.