Describe how email messages travel from sender to receiver.Include the names of the types of computers that are involved in the process,as well as the communications protocols that are typically employed.

When you send someone an email message,it travels across the Internet to the computer at your email service provider that handles outgoing email messages.This computer,called the outgoing email server,examines the email address on your message,selects the best route for sending the message across the Internet,and then sends the email message.Many outgoing email servers use SMTP (Simple Mail Transfer Protocol),which is a communications protocol,or set of rules for communicating with other computers.An email program such as Outlook contacts the outgoing email server and then transfers the email message(s)in its Outbox to that server.If the email program cannot contact the outgoing email server,the email message(s)remains in the Outbox until the program can connect to the server.
As an email message travels across the Internet,routers direct the email message to a computer at your recipient's email service provider that handles incoming email messages.A router is a device that forwards data on a network.The computer handling incoming email messages,called the incoming email server,stores the email message(s)until your recipient uses an email program such as Outlook to retrieve the email message(s).Some email servers use POP3,the latest version of Post Office Protocol (POP),a communications protocol for incoming email.