Which protocol is used to send email messages?

The appropriate protocol used to send email messages is Simple Mail Transfer Protocol (SMTP). SMTP is specifically designed for sending and routing email messages between servers. It operates on a client-server model where the client submits the email to the server, and then the server forwards it to its destination.

SMTP is used primarily for sending emails, whereas other protocols like IMAP (Internet Message Access Protocol) and POP (Post Office Protocol) are utilized for retrieving and accessing emails from the mail server. FTP (File Transfer Protocol) is not related to email but instead is used for transferring files over the internet, while HTTP (Hypertext Transfer Protocol) serves to transfer hypertext pages, typically used on the web.

Understanding SMTP’s role in the email communication process is crucial since it forms the backbone of email transmission, facilitating the sending and forwarding of messages across the internet.