Appendix Glossary E

In the left margin you will find links to the glossary categorised alphabetically. Some of the pages are quite long and may take a few moments to load if you use a modem. This glossary is always being updated.

Glossary - E

EAX - Environmental Audio Extensions. Environmental Audio is a system developed by Creative that recreates and delivers real-world, interactive audio experiences on the PC. Environmental Audio goes beyond today's surround-sound and 3D positional audio to actually model an environment with powerful effects that take into account room size, acoustic properties, reverb, echo and many other effects that create a real-world experience.

E Book - A book available for downloading to a computer via the Internet. Stephen King recently made Riding The Bullet, a short horror novel, available free on amazon.com. In some cases, special software such as Adobe Acrobat is required to accommodate the material. The possibilities with e-books are enormous as information requiring periodic updating (such as college textbooks) could be easily published online and downloaded by students as needed.

ECC - (Error Correction Code) A method of checking the integrity of data in DRAM. ECC provides more elaborate error detection than parity; ECC can detect multiple bit errors and can locate and correct single bit errors. Acronym for Error Correction Code. The incorporation of extra parity bits in transmitted data in order to detect errors that can be corrected by the controller.

E Commerce - Short for electronic commerce. A business that offers goods and services, as well as having the ability to accept payment for them, online. Many conventional brick and mortar companies are presently scrambling to establish an online presence and capitalise on the hoopla associated with being an ebusiness.

ECP - (Extended Capabilities Port) A kind of parallel port for PCs that allows for rapid bi-directional communications with devices such as a printer.

EDI - (Electronic Data Interchange) The exchange of information between two or more companies with mutual interests over a network.

Edit - To make changes in a file using one or more of the edit features available in an application.

Editor - A program similar to a word processing application that allows a user to create or modify text files.

Effector Key - A key, such as the Shift key, that when pressed, changes the function of another key.

EDO - (Extended Data Out) A DRAM technology that shortens the read cycle between memory and CPU. On computers that support it, EDO memory allows a CPU to access memory 10 to 20 percent faster than comparable fast-page mode memory. A type of memory popular in older Socket 7 motherboards. Some Super7 boards can use EDO memory, but many cannot. Consult your system's manual to ensure the right type of memory - they are many varieties. EDO is not capable of running at 100MHz FSB. If BX boards run under 66MHz FSB, EDO can be used.

EDRAM - (Enhanced DRAM) Enhanced Memory Systems, Inc. DRAM that contains a small amount of SRAM.

EEPROM - (Electrically Erasable Programmable Read-Only Memory) A memory chip that retains data content after power has been removed. EEPROM can be erased and reprogrammed within the computer or externally.

EGA - This means Enhanced Graphic Adapter. The standard came after the CGA. It gave more colours than the CGA and easier to read text. This standard has been superseded by the VGA.

EIDE Enhanced IDE. The enhanced version of IDE that is now standard on all PCs. Usually used interchangeably with the term "IDE." A maximum of four IDE devices can be connected to your PC's two internal IDE connectors: a primary master and slave (e.g., hard drive, CD-ROM) and one or two secondary channel devices (e.g., two more hard drives), which must also be configured as master and/or slave. High-performance devices are generally best configured as a "master."

EISA - (Extended ISA) A bus architecture that extended the 16-bit ISA bus to 32 bits. EISA operates at 8MHz and has a peak data transfer rate of 33 MB per second. EISA was introduced in 1988 as an open alternative to IBM's proprietary Micro Channel bus.

E-Mail - "Electronic Mail" An application of network connectivity and a communication standard to allow users on different computers to send messages (usually text only) back and forth. E-mail works in an analogous fashion to traditional paper mail. To compose an e-mail document, the user drafts a message and puts it in an electronic "envelope." This message is then delivered to the electronic "post office" (actually a computer acting as a mail server) that is responsible for that user. Upon receipt of the message, the "post office" decodes the electronic envelope and gleans from it which "post office" or mail server is responsible for the person defined as the recipient. The "post offices" then exchange the contents of the message, which is then handed off to the recipient by that person's local mail server. The only real problem with this model is that the mail servers will occasionally become "disgruntled" and fail to deliver the messages as instructed.

Embedded Command - A pre-programmed sequence of characters within a document that causes the document to display and consequently print out in a particular way.

Embedded Font - A type style that is included within a file to ensure that the printer has the proper resources available when the time comes to reproduce the document.

Embedded Object - An object included in a file that was created using a different software application, yet still has a link to the authoring software.

Embedded Servo - A timing or positioning signal included on the disk's surface that also stores data, allowing the actuator to fine tune the position of the read/write heads.

Embedded System - A microprocessor that functions independently of a computer. Automobiles, telephone equipment, satellites and a number of everyday appliances contain embedded systems that perform important functions for the device. For example, an automobile's imbedded microchip might be responsible for letting the owner know when routine maintenance is due.

Emoticon - Emoticons, or smileys :-) , are used to convey emotion. The expressions and inflections of voice we use to convey emotion, irony, sarcasm, etc. when talking are lost when communicating over the Internet. To make up for that, a system of symbols has developed which uses common keyboard marks.

EMS - This means expanded memory specification. It is a standard for accessing extra memory on all types of computers. This memory is used by DOS and most DOS applications.

Emulation - The resources of a program or a device to imitate another program or device. Often, lesser-known printers are designed to emulate some of the more common printers so they can share drivers.

Encoding - The protocol by which particular data patterns are changed prior to being written on the disk surface as a pattern of On and Off or 1 and 0 signals.

Encryption - One of many methods of securing data by encoding information so that it is only able to be read by the individuals or computers it was intended for. Usually a keyword or passcode is necessary to access the data.

Energy Star - Guidelines proposed by the Environmental Protection Agency in the early 1990s designed to reduce the amount of energy used by Personal Computers.

Environment - The condition of a computer or computer system as determined by several factors including the hardware and operating software it is running. For example, Windows compatible applications run in the Windows environment.

EOS - (ECC on SIMM) An IBM data-integrity-checking technology that features ECC data-integrity-checking on a SIMM.

EPIC - Explicitely Parallel Instruction Computing. EPIC is a fancy acronym that Intel invented to obfuscate the fact that they do not want the public appearance that their Merced microprocessor is actually a VLIW design. After all, Intel didn't invent VLIW, therefore they don't want to be publicly associated with a VLIW design.

EPROM - (Erasable Programmable Read-only Memory) - A programmable and reusable chip that retains content until erasure under ultraviolet light. Special equipment erases and reprograms EPROMs.

EPROM - Acronym for erasable programmable read only memory. An integrated circuit memory chip that can store programs and data in a non-volatile state. These devices can be erased by ultraviolet light and reprogrammed with new data. External drive - A drive mounted in an enclosure, separate from the computer system enclosure, with its own power supply and fan, and connected to the system by a cable.

EPROM - Erasable Programmable Read-only Memory (erasable by exposure to UV light).

EPS - "Encapsulated PostScript" EPS is a highly popular format for storing digital graphics for use in preparing documents for print. An EPS file contains the complete definition of a given image in the PostScript language that is used by the output device, in addition to a screen-based preview image built right in. It's even better than a shampoo with a built-in conditioner.

Ergonomics - The science of developing equipment and working environments that are safe, comfortable and efficient for humans. Ergonomics evaluates the design of machines and workspaces with the goal of reducing muscle and eyestrain. Ergonomic concerns also address proper posture and seating to reduce neck and back strain, mouse and keyboard position to minimise the occurrence of carpal tunnel syndrome, as well as monitor placement, and lighting.

Escape Key - This is a key on the keyboard with ESC on it. It is used by many programs as a way to cancel or exit out of the program.

ESCD - (extended system config. data): A four-kilobyte area of memory at hexadecimal offset 1D000h-1DFFFh. This area is used as NVRAM for PNP BIOS and PNP OS. Intel's ICU also uses ESCD to store information for PNP ISA cards and legacy ISA cards. Typically, you can choose to update ESCD (or not) by setting a BIOS option from the menu of "CMOS Setup" choices accessible at start-up time.

ESDRAM - (Enhanced Synchronous DRAM) - A type of SDRAM developed by Enhanced Memory Systems, Inc. ESDRAM replaces expensive SRAM in embedded systems and offers comparable speed with less power consumption and lower cost.

Ethernet - Ethernet is a popular hardware architecture and networking protocol that is used to connect computers together in a LAN. By maintaining a high-bandwidth physical connection between devices, Ethernet affords very high data transfer rates within a LAN. This means, for example, that those "Joke of the Day" e-mails will really fly if you send them to co-workers within the building. Ethernet is a networking standards originally developed in 1973 by Xerox and formalised in 1980 by DEC, Intel, and Xerox which transmits data at 10 MBps using a specified protocol. The most popular Local Area Network (LAN) technology in use today.

Ethernet address - Each Ethernet network node has its own unique Ethernet address that is obtained automatically when an Ethernet adapter is added to the computer. This number identifies the node as a unique communication item and enables direct communications to and from that particular computer.

EtherTalk - The AppleTalk network system used with an Ethernet network.

Even Parity - A type of data integrity checking whereby the parity bit checks for an even number of 1s.

Example - Click here to jump to the top of the page.

Exe File - The .EXE suffix tells the computer to open or execute a particular file.

Execute - To carry out a command.

Expanded Memory - This is extra memory in the computer which is needed for DOS and lots of DOS applications. You must add this kind of memory by buying hardware and software for it.

Expansion Card - This is a piece of hardware that is plugged into the main (mother)board of the computer. It expands the capability of your computer, and allows you to add new devices. You can add modems, sound cards, and stuff like that !

Expansion Slot - This is the location on the motherboard where the expansion card "sits" in. Typical computers have eight expansion slots into which daughter cards plug into.

Export - To save a file in a manner that allows it to be opened in another application. In many Windows programs selecting the "Save as" option under the File drop down menu offers many choices for saving work in other applications. For example, documents created in Microsoft Word can be formatted for use in Word Perfect and Macintosh.

Extended Memory - This is extra memory in an 80286 or 80386 computer. It is not expanded memory. It can be converted to more usable expanded memory with special software.

Extension - The suffix or the characters following the period in a filename such as mountain.jpg. This file might be a photograph (or other graphical representation) of a mountain in the form of a bitmap. The name "mountain" indicates that the file contains the image, and jpg indicates the type of file, which in this case is a bitmap. The software application a computer is currently running must be configured to execute particular file formats or they will be rejected.

External Viewer - A program associated with a Web browser that allows the user to look at an image or graphic presented in a particular format. Adobe Acrobat is an external viewer.

Extranet - Another variation on the theme of the Internet is represented by the term "extranet." Extranet does not represent a separate concept from Internet (or even intranet), but rather a specialised application of the technology that comprises the Internet. An extranet is really just a collaborative extension of an intranet. While an intranet is typically used for communication strictly within an organisation, an extranet may expand access to individuals outside that company, such as vendors or clients. A pretty decent analogy would be to view the idea of extranet as the "closed circuit TV" of the Internet (notwithstanding the fact that there probably actually is somebody out there who really is doing closed circuit TV over the Internet).

Ezine - (e zine or e-zine) Often pronounced zine, an electronic magazine published on a Web page or distributed through email. Ezines cover many topics from computers and electronics to investing, sex and beyond.