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.