A European format for digital transmission analogous to the North American T1 or DS1. E1 has 2.048 Mb/s (i.e. 32 channels @ 64 kb/s). Compare that to the T1 which has 1.544 Mb/s (24 channels @ 64 kb/s). E1 and T1 lines can be interconnected for international uses.
Easter Egg
A small program, message, or image, usually humorous or trivial, that programmers hide within their applications.
Extended Binary-Coded Decimal Interchange Code. A character code for text files in mainframes, especially IBM's OS/390 operating system and S/390 servers. Each character is a byte, yielding 256 different characters. See character codes.
Extended Backus-Naur Form. A language used to define grammar elements of other languages. Variations of EBNF are used by the W3C to define things like HTML or XML.

The typical syntax to define a symbol in the other language is as follows: symbol ::= expression.

EG: An end tag is defined as follows: ETag ::= '</' Name S? '>'. (Where S is white space.)
Where N is a hexadecimal integer, the expression matches the character
in ISO/IEC 10646 whose canonical (UCS-4) code value,
when interpreted as an unsigned binary number, has the value indicated.
The number of leading zeros in the #xN form is insignificant;
the number of leading zeros in the corresponding code value is governed by the character encoding in use.

[a-zA-Z], [#xN-#xN] 
Matches any Char with a value in the range(s) indicated (inclusive).

[abc], [#xN#xN#xN] 
Matches any Char with a value among the characters enumerated.
Enumerations and ranges can be mixed in one set of brackets.

[^a-z], [^#xN-#xN] 
Matches any Char with a value outside the range indicated.

[^abc], [^#xN#xN#xN] 
Matches any Char with a value not among the characters given.
Enumerations and ranges of forbidden values can be mixed in one set of brackets.

Matches a literal string matching that given inside the double quotes.

Matches a literal string matching that given inside the single quotes.

expression is treated as a unit and may be combined as described in this list.

Matches A or nothing; optional A.

A B  or A , B
Matches A followed by B, in that order.
This operator has higher precedence than alternation; thus A B | C D is identical to (A B) | (C D).

A & B
Matches A and B, in any order.

A | B 
Matches A or B but not both.

A - B 
Matches any string that matches A but does not match B.

Matches zero or one occurence of A.
Concatenation has higher precedence than alternation; thus A? | B? is identical to (A?) | (B?).

Matches zero or more occurrences of A.
Concatenation has higher precedence than alternation; thus A* | B* is identical to (A*) | (B*).

Matches one or more occurrences of A.
Concatenation has higher precedence than alternation; thus A+ | B+ is identical to (A+) | (B+).

/* ... */
Repeat the input immediately to the output.
European Computer Manufacturers Association. A standards body in Switzerland. They are the vendor-neutral establisher of ECMAScript, which is equivalent to JavaScript (Netscape) and JScript (Microsoft).
Extended Capabilities Port. See parallel port.
Electronic Data Interchange. The exchange of structured information between computers according to agreed standards. The standard may be established between two entities or may follow the standards of larger bodies such as UN/EDIFACT, ANSI X.12, or UCS. EDI is being replaced by XML but some companies are fairly invested in EDI.
Extended Data Output Dynamic Random Access Memory. An improvement over conventional DRAM (i.e. DIMMs or SIMMs) ca. Jul. 1996. Conventional DRAM reads one byte at a time, whereas EDO DRAM reads blocks of memory at a time into an internal cache. This requires the cache controller to support a transfer mode known as pipeline burst.
Email address.
A PROM chip that can be erased with electricity. The chip is therefore not really ROM but is used as ROM. See also flash memory
Enhanced Graphics Adapter. A standard for video cards and monitors. It has a resolution of 640 x 350 pixels. See video standards.
Enhanced Integrated Drive Electronics. A type of expansion slot. It is an improvement on IDE, it is faster (4 to 16.6 Mb/s), can store more (up to 8.4 GB), and can support more devices (up to 4). It competes with SCSI. It is supported by Seagate Technologies. See ATA.
Executive Information Systems. Software that accesses a data warehouse to provide an executive with a concise quick report that can help them make executive decisions.
Enhanced Industry Standard Architecture. An improvement on ISA, it supports multi-processors and 32 bit data paths. It also still accepts older ISA cards. The other popular buses are 16 bit ISA and the 64 bit PCI.
Electronic Data Interchange
See EDI.
(1) The size of the current font.

(2) The width of the small letter "m" of the current letter, which is usually the same as the size of the current font.

(3) "—" Aka em dash, long dash. The length of an em dash is usually equal to the small letter "m" or the size of the font or twice that of an en dash. An em dash is not a hyphen (-). It is 0151 in ANSI decimal, 8212 in Unicode decimal, 2014 in Unicode hexadecimal, OPT+SHIFT+- as a MacOS shortcut, and &#8212 or &#x2014 as an HTML escaped character. See also http://www.alistapart.com/stories/emen/.
Editor MACroS. Emacs and vi compete for the position of most common common text editor for UNIX. Emacs was written in 1976 by Richard Stallman, Guy Steele, and Dave Moon.
embedded OS
An OS that is fused into electronic products such as mobile phones, pagers, fax machines, and other specialized devices. Examples are Java, MS Windows CE, and systems by Time Systems, Microware Systems Corp., and Psion Software.
electronic mail. Network or internet communication of text or ASCII rendered data between e-mail addresses which usually follow this format: username@domain.tld, eg gh@georghernandez.com. SMTP is used to send, POP is used to receive.
.emf. Enhanced Metafile. A graphic format for Windows. It supports vector objects, rasterized images, and text, and has 24 bit color.
Regular characters used to convey an idea visually. Some are viewed from the side. EG:
     :)    :-)     :^)

See also my article on Chat Room Shorthand.

"–" Aka en dash, dash. The length of an em dash is usually equal to the size of the small letter "n" or roughly half of an em dash. An em dash is not a hyphen (-). It is 0150 in ANSI decimal, 8211 in Unicode decimal, 2013 in Unicode hexadecimal, OPT+- as a MacOS shortcut, and &#8211 or &#x2013 as an HTML escaped character. See also http://www.alistapart.com/stories/emen/.
Encapsulated PostScript
See EPS.
In OOP (object oriented programming), this is the creation of a class that can create objects that are self sufficient and easy to use. That is the object should not need other objects to function and the object should hide the details behind its use. This is especially important for classes that have polymorphic members, i.e. members that have similar names, interfaces, and usages for other classes.
Speaking in code. The obfuscation of information to protect it from being intercepted and interpreted by anyone other than the sender and receiver. The prevalent methods of encryption uses keys to encrypt and decrypt. The most popular symmetric key method (where the same key is used) is DES. The most popular public key method (where two keys are used) is PGP.
ENcoder-DECoder. See codec.
End Of File
See EOF.
End of Line
See EOL.
End Of Message.
See EOM.
Enhanced Graphics Adapter
See EGA.
Enhanced Integrated Drive Electronics
Enhanced Parallel Port
EPP. See parallel port.
Electronic Numerical Integrator And Computer. The world's first electronic, large scale, general-purpose computer, activated at the University of Pennsylvania's Moore School of Electrical Engineering by John Presper Eckert (1919-1995) and John W. Mauchly (1907-1980) in 1946.

The project was also sponsored by the US Army. ENIAC had 18,000 vacuum tubes, 70,000 resistors, 5 million soldered joints, and consumed 160 kW of electricity. See also ABC.
(1) A large organization's computer system as opposed to a small network or individual personal computer.

(2) A large corporation as opposed to a small business/organization or an individual.
Enterprise Resource Planning
See ERP.
End Of File.  In databases, this is the position after the last record in the recordset. A character is often used to indicate the end of a file. In UNIX this is usually CTRL-D = ^D = 4 = x4 = EOT = End Of Transmission.
End Of Line. Indicates the end of a line of text. As far as ASCII is concerned EOL = End Of Line = NL = New Line = \n = 10 = xA = LF = Line Feed. The Unix "EOL" = \n, but the old Mac "EOL" = \r, and the Windows "EOL" = \r\n. See also whitespace.
End Of Message.
Enhanced Parallel Port. See parallel port.
Erasable Programmable Read Only Memory. A PROM chip that can be erased with UV light. The chip is therefore not really ROM but is used as ROM.
Encapsulated PostScript. A file format based on PostScript. Has 24 bit color. Can include a preview in TIFF, PICT, or WMF. Especially good for PS printers. Such a file will probably start with %!PS-Adobe-3.0
Entity Relationship Diagram. A graphical representation of the relationships between tables in a database. There are boxes  (representing the tables) connected by lines (representing the joins). There are frequently little symbols on or along the lines representing the join types. These are often used ins system design and analysis.
Enterprise Resource Planning. A term used by companies that refers to the broad set of activities that are managed by the business, including:
  • Product planning
  • Material and parts purchasing
  • Production and plant operations
  • Maintaining inventory
  • Interacting with suppliers
  • Tracking orders
  • Providing customer service
  • Financial, asset, and cost accounting
  • Human resources and personnel management
  • Archiving documents
Although the term ERP sounds like business babble the force behind it is today's marketplace expectations:
  • Lower total costs along the supply chain
  • Shorter throughput times
  • Minimal stock
  • Larger product assortment
  • Higher product quality
  • Greater delivery reliability
  • Better customer service
  • More efficient coordination of global supply, demand, and production
ERP is supported with multi-module application software that uses or is integrated into a database system. ERP systems developed from inventory control in the 1960s to MRP (Material Requirement Planning) systems in the 1970s to MRP II (Manufacturing Processes) system in the 1980s. The inclusion of areas like Engineering, Finance, Human Resources, and Project Management led to the usage of the term ERP. The current trend is to use the Internet, IRP (Intelligence Resource Planning), MRP III (Money Resource Planning), KM (Knowledge Management), and data mining.

Popular ERP product providers include SAP (and their R/3 application), Peoplesoft, and J.D. Edwards.
error handler
Routines within a program that are designed to deal with runtime errors. They usually identify the error, give a possible fix, and then resume the program by either retrying or skipping the error inducing event.
See codec.
Ethernet is the most popular scheme for forming a network. Ethernet was invented at Xerox Corporation's Palo Alto Research Center (PARC) in the late 1970s and early 1980s. Ethernet is standardized as IEEE 802.3 CSMA/CD (Carrier Sense Multiple Access with Collision Detection) of the OSI Data Link Layer. Ethernet has a base rate of 10 Mb/s consisting of packets no more than 1.5 kB. Ethernet can run on wide variety of media, including, UTP (aka CAT 5 or 10BASE-T), thinnet coaxial cable (10BASE-2), thicknet coaxial cable (10BASE-5),a and fiber optic cable (10BASE-F). See my articles on Media and LANs.
Extract, Transform, Load. Conceptually what is done with data for databases and warehouses. Extract data from somewhere, somehow. Transform the data or morph it to what's needed. Load it to somewhere, somehow. See also CRUD.
Extended Three Letter Acronym.
Extreme UltraViolet Lithography. The etching of microchips using ultraviolet wavelengths and mirrors instead of optical lithography which uses visible light wavelengths and refraction. EUVL should be able to break the 0.1 micron etching limitation of optical lithography. As of 2000, optical lithography can achieve results of down to 0.25 micron etching.

EUVL should be able to make chips hundreds of times more powerful and memory chips store thousands of times more data. The limitation is the quality of mirrors attainable. EUVL is supposed to be available by 2025.
event-driven programming
A style of programming where different sections of code are executed in response to particular events, eg clicking a button,  performed by the user, the system, other applications, or even from elsewhere within the application. In general objects are created that are backed up by event procedures.
event procedure
A block of code that gets executed when particular events occur, such as clicking a button.
A text editor common on UNIX systems.
Microsoft Exchange. A groupware application suite made by Microsoft. The difference between Microsoft Exchange and Lotus Notes is that Notes has more application development facilities whereas Exchange is meant to be used more for its built in groupware apps like email, calendaring, and such.
Exchangeable image file format
See Exif.
.exe. Executable. A file that can run as an application.
Executive Information Systems
See EIS.
Exchangeable image file format. A specification for including digital camera metadata within files such as JPG, TIFF, and RIFF, but not PNG. The Exif standard was written by the Japan Electronic Industry Development Association (JEIDA).
expanded memory
RAM beyond the first 1 MB accessed via expansion cards on older PCs. See also extended memory.
expansion slots
Slots in the back of a computer system where modem cards, communication cards, video cards, sound cards, and other cards and components that expand the capabilities of the system.
The common kinds of expansion slots, from oldest and slowest, are AT bus (aka expansion bus), ISA slots, Micro Channel bus, EISA slots, VESA Local Bus (VLB), and PCI (currently the most common).
A part of a statement which combines values into new values through the use of operators. In most programming languages, expressions are symbols and operators that evaluate to a single data value. In SQL, an expression evaluates a single data value for each row in the result set. EG: SELECT ID, 1+2, price*2 FROM TableA.
Extended Backus-Naur Form
Extended Binary-Coded Decimal Interchange Code
Extended Capabilities Port
See parallel port.
Extended Data Out DRAM
extended graphics array
See XGA.
extended memory
RAM beyond the first 1 MB in PCs. See also expanded memory.
The capability to extend the different kinds of functionality a system has. This is in contrast with scalability, which is the capability to increase the volume of work that a system can handle.
extensible markup language
See XML.
extensible style sheet language
See XSL.
Files that modified the operating system at startup to increase functionality. For the Mac OS prior to System 7, these were known as INITs or Startups.
An intranet accessed by another intranet. Usually the two intranets are from different enterprises. Extranets are a key element in B2B.
extreme programming
See XP.
Extreme UltraViolet Lithography

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