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List of Defined Words
DS-1 and DS-3
Dates, ISO 8601
Domain style name
Dots per inch
Echo or Echoplex
File Identifier or Fileid
Fixed Pitch Fonts
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- DS-1 and DS-3
- Digital Switching; the transmission standards used on T1 and T3 lines,
respectively; see also T1 and T3.
- Defense Advanced Research Projects Agency: The US government agency that
funded research and experimentation which lead to the Internet network. See
- Direct Access Storage Device. A data storage device such as a magnetic
disk storage unit which allows the operating system to directly access specific
data stored on it without having to read through the data before it. This
is as opposed to a sequential access device such as magnetic tape.
- See File.
- Dates, ISO 8601
- See ISO 8601 Dates.
- The process of finding and eliminating software or hardware "bugs" (errors).
- The assumed value or action taken when no explicit one is specified.
- A text formatting term: The portion of any character which extends below
the baseline. See also Ascenders and Baseline.
- Dial-up lines
- A telephone line reserved for communication between the computer and remote
terminals. When you call a dial-up line, the computer answers and a connection
is made which enables you to logon to your account. Dial-up lines enable you
to use a computer system from any location that has a telephone, a modem or
coupler, and a terminal or a microcomputer running a terminal emulation program.
- Disk Drive
- A very fast input/output device that consists of one or more spinning magnetic
disks. A moving arm allows direct read or write access to data recorded on
- The DISSPLA graphics package is a library of FORTRAN subroutines. It was
designed to be used by scientific and business programmers. The DISSPLA library
routines must be called from a user written and executed program (written
in FORTRAN, or another higher level language such as Pascal or PL/I that supports
FORTRAN subroutine calls). See the Inform DISSPLA
- Distributed computing
- See client-server computing.
- Domain Name System or Service. The Internet service that translates Internet
domain names to IP addresses. For more information, see internet.com's PC
Webopaedia on DNS. See also IP address.
- Domain style name
- See Internet address.
- Disk Operating System: The name of the operating systems on most brands
of personal computer contains the acronym DOS. Often when DOS is used without
further description, the operating system being referred to is either PC DOS,
the operating system used to be used on most IBM personal computers, or MS
DOS, the variety of DOS that runs on IBM compatible computers.
- Dots per inch
- See Resolution.
- To transfer information stored in a remote computer to your (local) microcomputer.
- When information is passed from one type of device to another, usually
the electrical and mechanical requirements of the two devices are different;
software drivers are used to translate data which is to be sent another device
so that device can properly process it. (For example, a printer specific driver
may be used to prepare a document formatted by a word processing package for
printing on different types of printers, or the same printer used in different
- (1) A text formatting term: Printing on both sides of the paper. (2) A
computer communications term: Half duplex: data transmission in only one direction
at a time; and Full duplex: simultaneous data transmission in both directions.
- A type of broadband data transmission
that uses standard copper telephone lines; see Connecting
- Data Set Ready: When using DCE (Data Communications Equipment; a modem
is a common example), the DSR indicates that the DCE is ready to use.
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- Extended Binary Coded Decimal Interchange Code: A scheme of assigning characters
to each of the 256 possible combinations of 8 bits (1 byte). Several other
schemes are also used, such as BCD and ASCII.
- Echo or Echoplex
- Governs the appearance of characters on your VDT screen. Echo on means
that the characters are sent back to the screen by the receiving computer;
Echo off means that they are not.
- An interactive program that allows you to input, update, delete and store
information on the computer. The information may be programs, data, or actual
textual material such as letters or dissertations.
- Electronic Form
- A text formatting term: The name that Xerox systems uses for a predefined
graphic overlay form. The must common use of an overlay at UIC is to print
a departmental letterhead. Departments may contact the ACCC to arrange to
have a letterhead overlay developed for their departments.
- Electronic Mail
- A computer system which allows users to exchange messages, notes and files.
See the ACCC Email page. See also
POP and IMAP.
- Electronic Industries Association: A standards development organization
for electrical and functional characteristics of interface equipment.
- EPS Encapsulated PostScript File
- A file format for describing graphics and page segments for PostScript
- Email account
- Traditionally, an email account is a computer on which you receive mail
and an id that identifies your account on that computer. Maildrop is a newer
term that means pretty much the same thing as email account. POP account is
also similar, but a bit more specific -- it says that you'll use a POP server
to retrieve your incoming mail. (Eudora talks about "your POP account" in
its manuals and online helps.)
- These days, an email account might be just that -- an account that only
gives you a maildrop for incoming mail, without a standard computer account
that you can "login to." In the UNIX world, the "login to and do computer-type
stuff on" type of account is called a UNIX shell account. An
ACCC UNIX account is a UNIX shell account, as well as serving as your maildrop.
See the ACCC Accounts page for more
information on ACCC accounts and on opening yours.
- Email address
- has the form "person id" at "domain id." For example, the email address
of Ada Byron's account on tigger is firstname.lastname@example.org. In this email
address, Ms. Byron is identified by her tigger login id, adabyron, and tigger
is identified by its Internet domain name, tigger.cc.uic.edu.
- It's tempting to think that the "person id" part of an email address has
to be some person's login id on some computer and the "domain id" has to be
that computer's Internet domain name. That is often the case, but not always.
Consider the perfectly valid email address: email@example.com. "Consult" is
neither a person nor a login id. "uic.edu" is a computer, but neither consult
nor anyone else who uses a "firstname.lastname@example.org" email address has an account on
that computer. See also Netid.
- Email program
- the program or package that you use to read and reply to, save or delete
incoming mail messages, and to send mail messages of your own. Mail programs
are called "user agents" in the official descriptions of MIME -- Multipurpose
Internet Mail Extensions. (See Making
Email Talk in the September/October 1996 issue of The A3C Connection.)
The ACCC recommends three email programs -- Eudora
(for Windows and the Mac), WebMail (which
only needs a Web browser), and Pine (for
- See Smilie.
- Using software which makes a PC behave as though it were a terminal, or
which alters the characteristics of a user's terminal to act as a different
type of terminal.
- To convert data into a form which is acceptable for some piece of computer
equipment or task. See also compression
- To make temporarily unreadable. Datasets can be encrypted to ensure privacy.
See the A3C Connection article on encryption at: http://www.uic.edu/depts/accc/newsletter/adn16/encrypt.html
- Baseband protocol and technology for the cables and specialized circuitry
which is used to physically connect the machines on medium speed (10 Mbps)
local networks. Ethernet uses CSMA/CD (Carrier Sense Multiple Access with
Collision Detection). In plain English, this means that ethernet is a "broadcast
medium", similar to a party line telephone: every machine on a particular
Ethernet network looks at the Ethernet address on each packet as it goes by
to see if it is for them. When a transmitting data station on an ethernet
detects another signal being transmitted (a "collision"), it stops sending,
sends a jam signal, and then waits for a variable time before trying again.
For more information, see internet.com's PC
Webopaedia entry on ethernet. See also Fast Ethernet.
- Eudora is an email reading program, one of three that are supported by ACCC
at UIC. (Pine for UNIX and WebMail
for any Web browser are the other two.)
- Electronic Visualization
Laboratory at UIC, which advances research in computer graphics and interactive
techniques through a unique interdisciplinary blend of engineering, science
and art, offering advanced degrees through the UIC Electrical
Engineering and Computer Science department and the UIC
School of Art and Design.
- EXecute Channel Program: The execution of a program in the channel (see
Channel). The number of EXCP's in a job is
generally the number of blocks of data sent or received from input/output
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- Fast Ethernet
- 100 Mbps Ethernet, also for LANs.
- Fiber Distributed Data Interface: An ANSI standard specifying a higher
speed (100-Mbps) token-passing network using fiber-optic cable and a dual-ring
architecture to provide redundancy.
- Fiber-optic cable
- A thin, flexible cable which conducts modulated light transmissions. It
is more expensive than other types of network cabling, but it is not susceptible
to electromagnetic interference and is capable of higher data transmission
speeds. The ADN-ii uses fiber-optic cable.
- A collection of information stored in any of numerous forms on any of numerous
devices. A file may contain programs, data, or text. (In the very old days,
on MVS, files were called datasets.)
- File Identifier or Fileid
- The name of file on CMS.
- File server
- A device holding files which are available to everyone connected to a LAN.
The file server's software allows it to provide the machines on the LAN with
remote disk drives which function as if they were attached directly to their
machine. Examples of file server software are Microsoft's LAN Manager, IBM's
LAN Server, and Novell's NetWare.
- A protocol (an on UICVM CMS and on the public personal computers a command)
which allows you to get information on people using computer systems on the
- Fixed Pitch Fonts
- A text formatting term: A font in which all the characters have the same
width (as in a mechanical typewriter). Also known as "mono-spaced fonts".
See also Proportional Fonts.
- A code word in electronic messages indicating a heated argument. Electronic
communications lack the clues given by the body or voice in more personal
methods of communication, are therefore much more easily misunderstood. See
- FLoating point OPeration: An operation is a computer action which is specified
by a single computer instruction or a high level language statement, and a
floating point operation is an operation made on a floating point number.
The time used for an average FLOP is a measure of a computer's speed (see
- Floppy Disk
- A small portable flexible magnetic disk used for data storage on many microcomputers.
Floppies come in 3 and a half and 5 and a quarter inch sizes, with several
densities and formats.
- FM Synthesis
- Creating sounds and musical tones by directly manipulating the frequency
of the audio signal.
- A text formatting term: The lines at the top or bottom of a page that contain
the page number, publication name, publication data, volume numbers, and so
- A text formatting term: A complete assortment of printer characters in
a particular type style, typeface, size and orientation. Most fonts include
letters, numbers, punctuation and some special symbols. Note that the Roman
(normal), Italic, Bold and BoldItalic typeface forms of any type style and
size are each separate fonts.
- A font family is a complete set of characters in the same type style, including
all sizes and typefaces, such as bold, italic, underline, et cetera.
- A text formatting term: One or more lines of text that appear at the bottom
of every page.
- The interactive portion of the a computer system; e.g. when you are using
CMS interactively, your commands are executed in the foreground, when you
- FORmula TRANslating language: An old but still very common programming
language used in the scientific field. FORTRAN was the first high-level language
to become widely used. See Programming Languages
at the ACCC.
- File Transfer Protocol: A protocol in the Internet suite which allows a
user on any computer to get files from another computer, or to send files
to another computer. FTP is used for file transfer on the ADN-ii network.
See A Quick Introduction to FTP. See also
- Full Screen
- This term refers to the ability of a system to manipulate and edit the
text on the screen as a whole, as opposed to one line at a time.
- Full duplex
- A method of communication between two computers (or devices) that enables
simultaneous transmission in both directions.
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- A protocol translating device (software and hardware) used to pass information
from one network, with its set of protocols, to another network, which may
have a different set of protocols. In computer networks, gateways refer to
sites which belong to two or more networks allowing data to "cross over" from
one network to another. See also Bridge.
- Generic Font
- A text formatting term: A representation of alpha-numeric characters on
a screen that may not reflect what the final characters will look like. Utilities
that allow the viewing of printer formatted text on your screen generally
use generic fonts.
- GIF Graphics Interchange Format
- A color image transfer protocol developed by CompuServe.
- Gigabit Ethernet
- The newest version of Ethernet, which supports data
transfer rates of one gigabit (1,000 megabits) per second.
- Waterloo Generalized Markup Language, GML, a text formatting package that
was on CMS.
- Internet Gopher is a set of client-server protocols which provides a distributed
information delivery system around which a world/campus-wide information system
(CWIS) can readily be constructed. Most World Wide Web browsers support Gopher,
but it is rarely used any more.
- General Purpose Simulation System: A powerful general purpose simulator
which provides a wide range of capacities for discrete system modeling.
- A generic term used to describe the pictorial representation of data. Graphic
devices include printers, plotters, or special terminals.
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- Half duplex
- A method of communication between two computers (or devices) that allows
transmission in only one direction at a time.
- An exchange of predetermined signals between two computers or between a
computer and a peripheral device such as a modem or a printer. Handshaking
allows the computer to ascertain whether another device is present and ready
to transmit or receive data.
- Hard copy
- Usually hard copy means paper, but presumably can mean any printed computer
output, such as microfilm.
- The physical devices that make up a computer system.
- Hard disk
- A magnetic disk storage device used on larger microcomputers. Hard disks
are similar to the disk storage on mainframes, and are permanently installed
in the micro.
- (1) A text formatting term: One or more lines of text that appear at the
top of every page of a document. (2) A computer communications term: Control
information which is added before data when it is encapsulated for network
- An online system of information about various commands and programs, available
on all of our mainframe interactive systems, and also internally in many interactive
- A computer which is used for general computing purposes, which is also
connected to a network.
- Hierarchical Storage Manager: The automatic archiving system used on MVS
at the ACCC.
- HyperText Markup Language, the lingua franca of the WWW. A particular instance
of an SGML markup language, particularly suitable
for using hypertext pointers. For more information, see the Inform Internet
and the WWW menu.
- HyperText Transport Protocol. The rules by which WWW browsers and servers
- HTTP Daemon, the server side of the WWW client/server equation.
- Generally, a device which serves as the center of a star shaped network.
In Ethernet/IEEE 802.3 networks, a hub is an Ethernet multiport repeater (a
- Nonlinear multimedia, with hypertext navigational links, nodes, and controls.
- A text formatting term: Breaking up words at syllables or other natural
dividing points so that the lines of text are properly balanced. Hyphenation
can be achieved in several ways: some programs let you manually insert discretionary
hyphens which are only visible when they fall at the end of a line of text,
some programs insert hyphens automatically based on a dictionary of words,
and some programs use a logic formula or algorithm to hyphenate words.