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Computer, Telephony & Electronics
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An industry abbreviation for Electronically acceptable or Electrically acceptable.
The European equivalent of a T1 circuit. It is a term for a digital facility used for transmitting data over a telephone network at 2.048 Mbps.
A designation for a particular kind of non-volatile memory.
The European equivalent of a T3 circuit. It is a term for a digital facility used for transmitting data over a telephone network at 34 Mbps.
The European equivalent of a T4 circuit. It is a term for a digital facility used for transmitting data over a telephone network at 274 Mbps.
While called a computer, the E6B is most like a slide rule. It is the pilot device for in-flight calculations. It has been around the aviation industry since the early 50's and is just as popular now as then. It is a simple device to use; it is also convenient for pilots since it is not electronic. The aviation industry is a giant sector of the electronics industry, and uses the category term avionics for devices common to it. We have emulated some of the E6B calculations in our Aviation Calculators and Converters for your online use.
E & M - Control (4 wire E & M), (the receive and transmit leads of the signaling system). An equipment signaling system usually used in PABX applications with a digital announcer. This interface control scheme is standard equipment on most systems' announcers.
An industry acronym for Emergency Assistance Request. This is usually an internal request within a company for technical assistance by their own support staff to assist with an end-user problem. Most of these problems are termed as BUGS by users and by the programmers as undocumented features. This is almost always higher in priority than an ER.
A wire conductor that terminates in the earth for electrical purposes. It is generally the negative side of the circuit and is most important in alternating current (AC) circuits. Chassis Ground is the general term used in direct current (DC) circuits.
EarthLink is a major player in the national ISP struggle. In our opinion one of the best in that they seem to be family oriented and low key in operation. They provide good national coverage for access by people on the move. See them at HTTP://WWW.EARTHLINK.NET. A very good service for the price!
An Easter egg is a small program or message, generally humorous in nature, that programmers hide within an application such as Microsoft Word or Excel. The path to finding the Easter eggs is not documented. As in life, some Easter eggs are rotten. The egg can be a virus that can be destructive. In the case of eggs, something "cute" is often not what it is cracked up to be.
Abbreviation of Extended Binary-Coded Decimal Interchange Code. Pronounced eb-sih-dik, EBCDIC is an IBM designed code set for representing characters as numbers. Although it is widely used on large IBM (and other compatible mainframe) computers, most other computers, including PCs and Macintoshes, use ASCII codes in one form or another. Please see our comparison of ASCII & EBCDIC.
Electronic money designed to be used over a network or stored on cards similar to credit cards. Ecash is still more of an idea than a practical reality, largely due to security concerns.
An acronym for Error Correction Code. An electronic method of checking the integrity of data stored in DRAM. ECC is a more elaborate error-detection method than parity; it can detect multiple-bit errors and can locate and fix single-bit errors. ECC usually uses three additional bits per byte of data (compared to one additional bit for parity). See ECC memory.
1. Acronym for Error Correction Code memory, a particular type of memory that includes special circuitry for testing the accuracy of data as it passes in and out of memory. Located on a SIMM for example, the ECC logic corrects single errors in each byte of SIMM data. If the ECC is optimized on a SIMM or DIMM, it is the use of a module addressing architecture that facilitates the use of the memory module by systems with ECC. ECC optimized memory modules do not have byte-write capability.
2. ECC memory improves data integrity by detecting errors in memory. An ECC scheme capability is partially determined by the sophistication of the "systematic code" employed. The systematic code is like a reference table that the memory system uses to determine whether or not the memory has returned the correct data. Every time data is stored in memory, this code is responsible for the generation of check bits which are stored along with the data. When the contents of a memory location is referenced, the ECC memory logic uses the check bit information and the data itself to generate a series of "syndrome bits". If these syndrome bits are all zeros, then the data is valid and operation continues. If any bits are ones, then the data has an error and the ECC memory logic isolates the errors and reports them in the operating system. In the case of a correctable error, the ECC memory scheme can detect single and double bit errors and correct single bit errors.
Ecommerce or Icommerce
Ecommerce (electronic commerce or easy commerce), I-Biz, often termed Icommerce (Internet Commerce), is the act of doing business on the Internet. It is most often associated with consumer to business activities, as opposed to business to business activities. It takes specialized business software running on an Internet website to enable Ecommerce. The most effective business sites are interactive with the customer, can take orders, allow selection variations and option and take payment, all in a secure and safe environment.
An industry acronym for a specialized ASCII character set called the Extended Character Set. The main differences are in the control characters and the decimal character representations of decimal 128-255. Also see our ASCII Information and Character Set and our ASCII Information and Extended Character Set.
An acronym for Enhanced Data GSM Environment; a wireless standard for RF cellular communications.
An acronym for Electronic Data Interchange. It's the electronic communication process of business transactions, such as orders, confirmations, invoices and payments, between two organizations. The EDI model and concept allows organizations with different equipment to connect.
Extended Display Identification Data is a VESA standard data format that contains basic information about a monitor and its capabilities, including vendor information, maximum image size, color characteristics, factory pre-set timings, frequency range limits, and character strings for the monitor name and serial number. The information is stored in the display and is used to communicate with the system through a Display Data Channel (DDC ), which sites between the monitor and the PC graphics adapter. The system uses this information for configuration purposes, so the monitor and system can work together. The latest version of EDID (version 1.3) can be used in CRT displays, LCD displays, and future display types because EDID offers general descriptions of almost all display parameters.
1. One of several programs on a computer used to create and modify text files. Other common editors include pure ASCII text editors (such as Microsoft's NotePad), HTML editors (such as CoffeeCup), various language editors (such as the environment in Visual Basic) and more. Word processing programs (such as Word and WordPerfect) are also editors.
2. The head honcho at a magazine, newspaper or portal that is responsible for the text and graphic presentation.
1. An acronym for Extended Data Out. A form of DRAM technology that shortens the read cycle between memory and CPU. On computer systems designed to support it, EDO memory allows a CPU to access memory 10 to 20 percent faster than comparable fast-page mode chips; sometimes called hyper page mode.
2. A DRAM performance feature that permits multiple bits of data in a single row to be accessed quickly. EDO involves selecting multiple column addresses in rapid succession once the row address has been selected. Once the first column address has been selected and CAS becomes active, the data output drivers are activated. The data output drivers remain active for each successive CAS strobe, until RAS goes high. Most EDO modules are non-parity but there are some modules of EDO design that are parity.
An acronym for Enhanced Definition TV, a 2003 adopted standard for something in viewing quality between the 525 conventional interlaced display and High Definition. The formal specification is 480p, often confused with 480i. Please see the other definitions of SDTV and HDTV for the overall picture (pardon the pun) on television.
A channel of most online services that specializes in education and online classes. Sometimes these are self help tutorials while others are online classrooms with regularly scheduled meetings.
An acronym for Electrically Erasable PROM, or Electrically Erasable Programmable Read-Only Memory. An EEPROM memory cell is physically larger than an EPROM cell but offers the advantage of being erased electrically without the added expense and trouble of a special UV eraser requirement. Also, an extra advantage of this type device is that EEPROM devices can be erased, even in much lower cost plastic packaging.
An electronic form that is filled out by a user and sent over a network. They are typically used to place orders or provide feedback. Eforms can be placed on web pages or in Java applets and usually contain text boxes, buttons, and other components.
An abbreviation for Extra High Voltage, a term meaning any amount of voltage in excess of 345,000 volts.
The abbreviation for Electronics Industry Association.
The term given in the early 1990s to rename the RS-232 recommended standard. See our detailed explanation of serial communications.
An acronym for Enhanced IDE, a newer version of the IDE mass storage device interface standard developed by Western Digital Corporation. The original concept was the offspring of ESDI technology. It supports data rates of between 4 and 16.6 MBps, about three to four times faster than the old IDE standard. In addition, it can support mass storage devices of up to 8.4 gigabytes, whereas the old standard was limited to 528 MB. Because of its lower cost, enhanced EIDE has replaced SCSI in many areas. (While data transfer rates approach SCSI, the offloaded CPU duties and number of devices is not up to the capability of SCSI.) EIDE is sometimes referred to as Fast ATA or Fast IDE, which is essentially the same standard, developed and promoted by Seagate Technologies. It is also sometimes called ATA-2. There are four EIDE modes defined. The most common is Mode 4, which supports transfer rates of 16.6 MBps. There is also a new mode, called ATA-3 or Ultra ATA, that supports transfer rates of 33 MBps.
1. An acronym for Effective Isotropic Radiated Power. The EIRP is the apparent power transmitted towards the receiver, if it is assumed that the signal is radiated equally in all directions, such as a spherical wave emanating from a point source. See our EIRP Calculator.
2. An industry slang reference to Ohm's Law, with power. See our Ohm's Law Calculations With Power.
An acronym for Enhanced Industry Standard Architecture. A well thought out computer expansion bus used in high end 386 and 486 PC's and some Techtronix and Hewlett-Packard Workstations. A non-proprietary industry-wide attempt to counter IBM's MicroChannel bus. (This lasted 7 years; when was the last time you saw a MicroChannel computer?) A bus width of 64 bits allowed a 33mbs transfer rate (fully 32 bit operational), making it ideal for file server computers with high disk I/O rates. Unfortunately the 8.25MHz bus speed made for high latency in small transfers, leading to poor video performance compared to the 32 bit, 33mhz VESA Local bus. To any extent, it was an effort by the industry to further technology and it worked beyond the original designers' wildest expectations. The PCI bus offered greater performance and capability. Initially PCI architecture was offered in conjunction with ISA boards. Now most systems are eliminating the ISA capability to gain additional performance. Those that still enable ISA are termed Legacy capable.
Electrodes are electrical terminals, normally left unconnected at one end. Electrical connection between electrodes is often made by electric arcing or holding them in salt solutions. There are two electrodes in every battery, one positive and one negative. Electrodes are conductive.
Electrons, as related to general electricity, are the flowing electrical current in a circuit. The ampere, or amp, is the measure of flow of electrons. One ampere flowing for one second of time passes a coulomb of charge along the wire. Electrons travel at a fairly constant speed, about 20 centimeters or 8 inches per nanosecond. They do NOT travel at the speed of light as is OFTEN incorrectly insinuated in text books.
Electronic Frontier Foundation
To quote their mission statement, "The Electronic Frontier Foundation is a non-profit civil liberties organization working in the public interest to protect privacy, free expression, and access to public resources and information online, as well as to promote responsibility in new media." Their WWW site is located at HTTP://WWW.EFF.ORG.
Electronic Paper or Epaper
Invented by Xerox at Xerox PARC, electronic paper (also known as epaper) is made from a new display technology called gyricon. A gyricon sheet is a thin piece of transparent plastic that contains millions of small beads. Each bead, half white half black, is contained in an oil-filled cavity and is free to rotate within its cavity. Epaper is electrically writable and erasable and can be re-used 1000s of times. When voltage is applied to the surface of the sheet, the beads rotate to display either their black sides or white sides. Images of pictures and text are created when a pattern of voltages are sent to the paper. The image will remain until the voltage pattern changes. Recently, Xerox chose office supplier 3M to help mass produce epaper, which should be ready for resale by mid-2000.
An ellipse is sort of a distorted circle; flattened a little and stretched a little. It is a set of points, all on the same plane that are somewhat egg shaped in a one dimension view. Check out the CSG Ellipse Circumference Calculator.
Electronic Mail, text files that are sent from one person to another. E-Mail can be sent to people online anywhere on the Internet. Unsolicited E-Mail is called junk mail. You WILL experience it. See mail.
An electronic mail address. E-Mail addresses follow the formula: user-ID@domain-name. Good form is associated with all lower case letters although some E-Mail systems now are more forgiving and will accept some or all upper case entries. The standard is lower case.
An application or program that runs on a personal computer or workstation and enables you to send, receive and organize E-Mail. It's called a client because e-mail systems are based on a client-server architecture. Mail is sent from many clients to a central server, which re-routes the mail to its intended destination. Microsft's Outlook (in one of several versions) is an example.
A fictitious "place" where lost E-Mail is said to wind up.
1. The state of being completely overwhelmed by the amount of E-Mail one has received.
2. A mail server under SPAM attack.
A specialized computer system that is part of a larger system or machine. Typically, an embedded system is housed on a single microprocessor board with the programs stored in ROM. Virtually all appliances that have a digital interface, watches, microwaves, VCRs, cars, utilize embedded systems. Some embedded systems include an operating system, but many are so specialized that the entire logic can be implemented as a single program.
1. An acronym for ElectroMotive Force, the term we use to describe anything which behaves like an electrical pump. Batteries, generators, thermoelectric devices, solar cells, and piezoelectric crystals all do the same job in an electrical circuit. They pick conduction charges up at points of low potential energy and lift them up to high potential energy. If we imagine that current is positive charge in motion, then an EMF pumps the current from low voltage up to high voltage. EMF is measured in volts.
2. An acronym for ElectroMagnetic Field. These fields are produced by power lines, transformers, appliances and radio frequency-RF sources such as microwave ovens, cellular phones, AM/FM/TV transmitters, radars,etc. During the last 15 years various scientific studies in the United States and in Sweden have demonstrated a statistically significant association between electromagnetic fields from power lines and certain types of cancers in both children and adults. An electromagnetic field, sometimes referred to as an EM field, is generated when charged particles, such as electrons, are accelerated. All electrically charged particles are surrounded by electric fields. Charged particles in motion produce magnetic fields. When the velocity of a charged particle changes, an EM field is produced. Electromagnetic fields were first discovered in the 19th century, when physicists noticed that electric arcs (sparks) could be reproduced at a distance, with no connecting wires in between. This led scientists to believe that it was possible to communicate over long distances without wires. The first radio transmitters made use of electric arcs. These spark transmitters and the associated receivers were as exciting to people in the early 20th century as the Internet is today. This was the beginning of what we now call wireless communication. Electromagnetic fields are typically generated by alternating current (AC) in electrical conductors. The frequency of the AC can range from one cycle in thousands of years (at the low extreme) to trillions or quadrillions of cycles (hertz) per second (at the high extreme). The standard unit of EM frequency is the hertz, abbreviated Hz. Larger units are often used. A frequency of 1,000 Hz is one kilohertz (kHz); a frequency of 1,000 kHz is one megahertz (MHz); a frequency of 1,000 MHz is one gigahertz (GHz). The wavelength of an EM field is related to the frequency. If the frequency f of an EM wave is specified in megahertz and the wavelength w is specified in meters (m), then in free space, the two are related according to the formula w = 300/f(mhz). For example, a signal at 100 MHz (in the middle of the American FM broadcast band) has a wavelength of 3 m, or about 10 feet. This same formula applies if the frequency is given in gigahertz and the wavelength is specified in millimeters (mm). Thus, a signal at 30 GHz would have a wavelength of 10 mm, or a little less than half an inch. You might also want to see our Communications Calculators, Converters and Tables and our Electronics Calculators, Converters and Tables for much more information.
One of the pins on a transistor, along with collector and base. The emitter is the point the transistor connects to the main circuit to return amplified signal voltage. It is the exit point from the transistor.
The online means of facial expressions and gestures. Examples: :) Tip your head to the left and you will see the two eyes and smiling mouth. Use them where applicable in chats and E-Mail. Other emoticons include the following; :( sad ; :0 surprised ;
o:) innocent ; and many others. Too much usage is considered poor style; they get old in a hurry! Also see our page on Text Messaging Shorthand which has MANY more in it.
1. A method of 'scrambling' a message using complex mathematical formulas. The message appears as gibberish to all except those in possession of the key to unscramble the message. This is a primary form of security.
2. A procedure that renders the contents of a message or file unintelligible to anyone not authorized to read it. PGP (Pretty Good Privacy) is a commonly-used encryption program.
A generic term describing an extremely large network. It is usually used as a definition of 500 stations or greater.
A channel of many online services that specializes in entertainment, games and having fun. It is considered poor style to admit to having fun on a computer.
An acronym for End Of Life. It usually refers to the time period of support for a software product after a new revision has been placed into use. From time to time, hardware vendors also use the term to describe a time period of support for a given hardware item.
An acronym for ECC on SIMM. A data-integrity checking technology designed by IBM that features ECC data-integrity checking built onto a SIMM.
An acronym from Intel for Explicitly Parallel Instruction Computing, which was designed to fully incorporate all of the features of the Itanium series of processors from Intel. The uniquely designed EPIC architecture allows the highest possible performance via new levels of parallelism for enterprise and technical applications. Enhanced floating point performance smooths analytic and scientific design and visualization applications. 64-bit addressing and massive resources combine to provide a platform to handle many terabytes of data with improved memory latency and fewer branch misses to further improve database performance. High availability and scalability and breadth of enterprise operating systems and applications ensure high performance from languages utilizing the capabilities.
A point marking the start of a new period in time. For UNIX type computers, it is 1/1/1970, GMT. This is associated with a term known as UNIX timestamp. See our handy converters to convert from or to Unix timestamp.
1. An acronym for Electrically PROM, or Electrically Programmable Read-Only Memory. Similar to the technology used in standard EPROM and PROM memory devices. Commonly used in both SPLD and CPLD devices. EPROM cells are electrically programmed in a device programmer. Some EPROM-based devices are erasable using ultra-violet (UV) light if they are in a windowed package. However, most EPROM-based SPLD/CPLDs are in low-cost plastic packaging for production. Plastic packages cannot be UV erased.
2. An acronym for Erasable PROM, or Erasable Programmable Read-Only Memory. This form of device is cleaned (de-programmed) by UV (ultraviolet) light in a device called a PROM eraser.
An industry acronym for Enhancement Request. This is usually an internal request within a company for technical assistance, hopefully ending in software (but possibly hardware) modifications by their own support staff. This is almost always lower in priority than an EAR.
An unanticipated event stemming from a hardware or software issue.
A message that indicates that there is a problem. When looking to solve these problems, it's important to remember the exact wording of these windows when seeking help from a provider or support source. Some error messages are less subtle than others; for instance, the hand reaching out from the monitor, smacking you thrice upon the head and shoulders generally gets your attention and is seldom forgotten when describing the message to the support person. Remember them when they are still somewhat subtle.
A modem protocol that will check data to make sure that the data being sent and the data being received are the same. Most ISPs support several forms of error-correction. Most LAN cards, also known as NICs (network interface cards), support similar protocols within their own environment. An often asked question is, "If they correct errors, why do we need error messages?" (Watch out for the hand!)
An acronym for Enhanced Small Device Interface, an early high performance interface standard developed by a consortium of the leading personal computer manufacturers for connecting disk drives to PCs. ESDI was two to three times faster than the older ST-506 (MFM) standard. To use an ESDI drive, your computer had to have an ESDI controller. Introduced in the early 80s, ESDI is long since obsolete but is the father of technologies such as SCSI, RLL, IDE, EIDE, AT and ATA interfaces.
An acronym and abbreviation for Electronic Serial Number, a term used with cellular phones primarily but with some PDA services as well. A 32 bit code that is unique to each mobile unit. It is used to validate mobile service. Not alterable by either cellular operator and end user, it is considered a secure ID. Each cellular phone is assigned an ESN which is automatically transmitted to the base station every time a cellular call is placed. The Mobile Telephone Switching Office checks the ESN to make sure it is valid, that the phone has not been reported stolen, that the user's monthly bill has been paid, and other checks, before permitting the call to go through.
ETACS is the analog section of cellular telephone service.
ETAS is the acronym for Encrypted Transaction Audit System. This technology, developed by Computer Support Group, is used within many business websites. I-Biz and Ecommerce software are to enable security and special transaction auditing and tracking. It works in conjunction with several other security packages to fully ensure safe and intelligent business transactions on the Internet.
Ethernet is a particular network topology and protocol, especially useful in LANs. It comes in various speeds and is often regarded as THE current technology for general network direct connection. A long time standard method of connecting computers to a local area network using coaxial cable, invented by Robert Metcalfe at Xerox PARC in the early 1970s. The current connectivity is generally considered to be 10Base-T or 100Base-T, while the backbone, if one is used, is coaxial cable or Fiber optics. There is also a 1000Base-T for certain specialty copper joining situations. You may also want to check out our bandwidth speed comparison.
ETSI, the European Telecommunications Standards Institute, is a non-profit organization whose mission is to produce the telecommunications standards that will be used for decades to come throughout Europe and beyond. Based in Sophia Antipolis, south of France, ETSI unites 912 members from 54 countries inside and outside Europe, and represents administrations, network operators, manufacturers, service providers, research bodies and users. The Institute´s work program is determined by its members, who are also responsible for approving its efforts. As a result, ETSI´s activities are maintained in close alignment with the market needs expressed by its members. ETSI plays a major role in developing a wide range of standards and other technical documentation as Europe´s contribution to world-wide standardization in telecommunications, broadcasting and information technology. ETSI´s prime objective is to support global harmony by providing a forum in which all the key players can contribute actively. ETSI is officially recognized by the European Commission. See them at WWW.ETSI.ORG.
A type of data integrity checking where the parity bit checks for an even number of 1's (as opposed to an odd number).
1. A number that is the equivalent of 2 to the 60th power (1,152,921,504,606,846,976) bytes; a quintillion (10 to the 18th power) in the American system. To put things is proper perspective, an exabyte is equal to 1,024 petabytes, also a billion billions, which I'm certain is much easier to understand. Also see zettabyte. Don't know your KB from your MB? Try our memory and storage converter. (Also see powers of ten, kilobyte, megabyte, gigabyte, terabyte, and yottabyte.)
2. A long-time manufacturer of mass storage devices. See them at WWW.EXABYTE.COM.
Microsoft's answer to Lotus 1-2-3. An excellent spreadsheet program that has migrated from DOS to the current Office 97 release, running in Windows 98, 95 and NT. The package is an integral part of the Microsoft Office Suite, in several versions and packaging options. It will import and export most other spreadsheet files; other Microsoft Office applications can also directly and indirectly share files. You can find out more information about Excel and other Microsoft applications through HTTP://WWW.MICROSOFT.COM
An Internet search engine and starting page service of excellent quality. Located at HTTP://WWW.EXCITE.COM. Has several services and features for the end user.
1. To process or run a computer program.
2. What you do to the person in charge of backups when your disk crashes and your most recent backup is a year old.
In programming, an expression is any legal combination of symbols that represents a value. Each programming language and application has its own rules for what is legal and illegal. If a compiler does not check for legality of an expression, an ILLEGAL OPERATION error message can occur at run time if an illegal expression is encountered. For example, in the C language x+5 is an expression, as is the character string "MONKEYS." Every expression consists of at least one operand and can have one or more operators. Operands are values, whereas operators are symbols that represent particular actions. In the expression "x + 5", x and 5 are operands, and + is an operator. Expressions are used in programming languages, database systems, and spreadsheet applications. For example, in database systems, you use expressions to specify which information you want to see. These types of expressions are called queries.
1. Macintosh files that add functionality to the system software.
2. On all platforms, the last 3 characters of a filename, as in COMMAND.COM, where COM is the extension. As data nomenclature structures have advanced to include long file names, this structure is not mandatory any longer except to conform to the operating system and downward compatibility.
3. Extensions are also utility functions, programs and routines that work with the native operating system and server function of a network server to allow additional functions. See our OTHER section of this glossary for many common and unusual file extensions.
4. A common group of function extensions work with Microsoft's Front Page product. Special website functions that Front Page can create may not work on a server until the extensions are loaded and running on that server.
The term generally accepted to mean business functions on the Internet along with whatever it takes to make them happen.
A viewing audience for a WWW site; visitors to a web site. See who is viewing this site.
An electronic media for viewing. See zine.
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