Lesson 7

Message Transfer Agent (MTA)

A messaging component that routes, delivers and receives e-mail.

Mail User Agent (MUA)

A messaging component used asa stand-alone application by the user.

Pretty Good Privacy (PGP)

A method of encrypting and decrypting e-mail messages. It can also be used to encrypt a digital signature.

Header

A block of information attached to a piece of data. The first part of a network packet. Can contain network addressing information or additional information that helps computers and applications process data.

Emoticon

A combination of characters that, when read sideways, helps convey emotion in an e-mail message.

Attachment

A file that is sent with an e-mail message.

Multipurpose Internet Mail Extensions (MIME)

A protocol that enables operating systems to map file name extensions to corresponding applications. Also used by applications to automatically process files downloaded from the Internet.

Blackhole list

A published list of IP addresses known to be sources of spam.

Personal Digital Assistant (PDA)

A small, handheld computer used for personal information management. The predecessor to the smartphone.

CAPTCHA (CompletelyAutomated Public Turing Test to Tell Computers and Humans Apart)

A test that uses a word-verification graphic designed to differentiate humans from automated senders during online transactions.

Personal information management (PIM) program

A tool used to schedule appointments and meetings, store contact information, and manage tasks.

User name

A unique name or number that identifies you when logging on to a computer system or online service. In an e-mail address, the part before the @ symbol.

IP address

A unique numerical address assigned to a computer or device on a network.

Spam filter

An e-mail client program that identifies and filters out spam messages before they reach the e-mail Inbox.

E-mail client

An e-mail program that is independent of any specific Web browser, and that you can use to send e-mail messages.

Mail Delivery Agent (MDA)

An e-mail server program that receives sent messages and delivers them to their proper destination mailbox.

GNU Privacy Guard (GPG)

An open-source version of PGP, used for encrypting and decrypting e-mail messages, that does not use patented algorithms.

Browser e-mail

E-mail programs such as Outlook, Express and Opera Mail that come bundled with a Web browser and with which they may be integrated.

Web-based e-mail

Free e-mail service from a provider such as Windows Live Hotmail or Yahoo! in which you request a user name. You can access your e-mail from any computer that has access to the Internet.

Secure MIME (S/MIME)

Secure version of MIME that adds encryption to MIME data.

Snail Mail

Slang term for the standard postal service.