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Definitions & Terms

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B8ZS - Bipolar 8-zero Substitution:

  • See - Bipolar 8-zero Substitution.

Backup Domain Controler - BDC

  • Primary domain controller (PDC) and Backup Domain Controller (BDC) are roles that can be assigned to a server in a network of computers that use the Windows NT operating system. Windows NT uses the idea of a domain to manage access to a set of network resources (applications, printers, and so forth) for a group of users. The user need only to log in to the domain to gain access to the resources, which may be located on a number of different servers in the network. One server, known as the primary domain controller, manages the master user database for the domain. One or more other servers are designated as backup domain controllers. The primary domain controller periodically sends copies of the database to the backup domain controllers. A backup domain controller can step in as primary domain controller if the PDC server fails and can also help balance the workload if the network is busy enough.
  • In Windows NT, a domain combines some of the advantages of a workgroup (a group of users who exchange access to each others' resources on different computers) and a directory (a group of users who are managed centrally by an administrator). The domain concept not only allows a user to have access to resources that may be on different servers, but it also allows one domain to be given access to another domain in a trust relationship. In this arrangement, the user need only log in to the first domain to also have access to the second domain's resources as well.
  • In a Windows NT network, not all servers need to be a PDC or BDC. A server can be designated as a member server whose resources become part of a domain without having a role in the logon process. Setting up and maintaining PDCs and BDCs and domain information is a major activity for the administrator of a Windows NT network. In Windows 2000, the domain controller concept is retained but the PDC and BDC server roles are generally replaced by the Active Directory.

Bandwidth Test:

  • A bandwidth test is a program that sends one or more files of known size over a network to a distant computer (for example, your own computer), measures the time required for the file(s) to successfully download at the destination, and thereby obtains a theoretical figure for the data speed between two or more points, usually in kilobits per second (Kbps) or megabits per second (Mbps).
  • Bandwidth test results vary greatly, even from moment to moment, and occasionally produce absurd or improbable figures. Factors that affect test results include:
  • * Internet traffic (speed generally decreases as volume increases)
  • * Variable propagation delays (can artificially inflate or degrade the result)
  • * Noise on data lines (has a real detrimental effect)
  • * The size(s) of file(s) used for the test
  • * The number of files used for the test
  • * The demand load on the test server at time of test
  • * Geomagnetic and/or thunderstorm activity
  • In order to get a reasonable estimate of bandwidth (sometimes referred to as throughput ), experts suggest that three or more different test sites be used, and that each test be conducted six times at each site. Then the top and bottom 1/3 of the figures should be disregarded. Finally, the middle 1/3 of the results should be averaged.


  • BASIC was an early programming language that is still among the simplest and most popular of programming languages. Originally designed as an interactive mainframe timesharing language by John Kemeney and Thomas Kurtz in 1963, it became widely used on personal computers everywhere. On IBM's first "family" computer, the PCJr, a BASIC cartridge was a popular add-on. Because of its simplicity, BASIC has frequently been used in teaching the introductory concepts of programming with a working language.
  • BASIC continues to be widely used because it can be learned quickly, its statements are easy to read by other programmers, and support is available on most operating systems. BASIC's documentation has been translated into many national languages. It often comes with sound and graphics support. A popular version of BASIC today is QBASIC.
  • BASIC is used in many business applications and is still considered a valid choice as a programming language for some purposes. Microsoft's Visual Basic adds object-oriented features and a graphical user interface to the standard BASIC.
  • The following example of BASIC gets a number from a user, multiplies the number by 10, and prints or displays the result:
  • 10 PRINT 'Enter a number'
  • 20 INPUT NUM
  • 30 PRINT 'Your number * 10 is ';NUM*10;

Basic Input Output System - BIOS:

  • BIOS is the program a personal computer's microprocessor uses to get the computer system started after you turn it on. It also manages data flow between the computer's operating system and attached devices such as the hard disk, video adapter, keyboard, mouse, and printer.
  • BIOS is an integral part of your computer and comes with it when you bring it home. (In contrast, the operating system can either be preinstalled by the manufacturer or vendor or installed by the user.) BIOS is a program that is made accessible to the microprocessor on an eraseable programmable read-only memory (EPROM ) chip. When you turn on your computer, the microprocessor passes control to the BIOS program, which is always located at the same place on EPROM.
  • When BIOS boots up (starts up) your computer, it first determines whether all of the attachments are in place and operational and then it loads the operating system (or key parts of it) into your computer's random access memory (RAM) from your hard disk or diskette drive.
  • With BIOS, your operating system and its applications are freed from having to understand exact details (such as hardware addresses) about the attached input/output devices. When device details change, only the BIOS program needs to be changed. Sometimes this change can be made during your system setup. In any case, neither your operating system or any applications you use need to be changed.
  • Although BIOS is theoretically always the intermediary between the microprocessor and I/O device control information and data flow, in some cases, BIOS can arrange for data to flow directly to memory from devices (such as video cards) that require faster data flow to be effective.

Bayesian Logic:

  • Named for Thomas Bayes, an English clergyman and mathematician, Bayesian logic is a branch of logic applied to decision making and inferential statistics that deals with probability inference: using the knowledge of prior events to predict future events. Bayes first proposed his theorem in his 1763 work (published two years after his death in 1761), An Essay Towards Solving a Problem in the Doctrine of Chances . Bayes' theorem provided, for the first time, a mathematical method that could be used to calculate, given occurrences in prior trials, the likelihood of a target occurrence in future trials. According to Bayesian logic, the only way to quantify a situation with an uncertain outcome is through determining its probability.
  • Bayes' Theorem is a means of quantifying uncertainty. Based on probability theory, the theorem defines a rule for refining an hypothesis by factoring in additional evidence and background information, and leads to a number representing the degree of probability that the hypothesis is true. To demonstrate an application of Bayes' Theorem, suppose that we have a covered basket that contains three balls, each of which may be green or red. In a blind test, we reach in and pull out a red ball. We return the ball to the basket and try again, again pulling out a red ball. Once more, we return the ball to the basket and pull a ball out - red again. We form a hypothesis that all the balls are all, in fact, red. Bayes' Theorem can be used to calculate the probability (p) that all the balls are red (an event labeled as "A") given (symbolized as "|") that all the selections have been red (an event labeled as "B"):
  • p(A|B) = p{A + B}/p{B}
  • Of all the possible combinations (RRR, RRG, RGG, GGG), the chance that all the balls are red is 1/4; in 1/8 of all possible outcomes, all the balls are red AND all the selections are red. Bayes' Theorem calculates the probability that all the balls in the basket are red, given that all the selections have been red as .5 (probabilities are expressed as numbers between 0. and 1., with "1." indicating 100% probability and "0." indicating zero probability).
  • The International Society for Bayesian Analysis (ISBA) was founded in 1992 with the purpose of promoting the application of Bayesian methods to problems in diverse industries and government, as well as throughout the Sciences. The modern incarnation of Bayesian logic has evolved beyond Bayes' initial theorem, developed further by the 18th century French theorist Pierre-Simon de Laplace, and 20th and 21st century practitioners such as Edwin Jaynes, Larry Bretthorst, and Tom Loredo. Current and possible applications of Bayesian logic include an almost infinite range of research areas, including genetics, astrophysics, psychology, sociology, artificial intelligence (AI), data mining, and computer programming.

Bayonet Neil-Concelman - BNC:

  • See BNC.

BDC - Backup Domain Controler

  • See Backup Domain Controller


  • In its JavaBeans application program interface for writing a component, Sun Microsystems calls a component a "Bean" (thus continuing their coffee analogy). A Bean is simply the Sun Microsystems variation on the idea of a component.
  • In object-oriented programming and distributed object technology, a component is a reusable program building block that can be combined with other components in the same or other computers in a distributed network to form an application. Examples of a component include: a single button in a graphical user interface, a small interest calculator, an interface to a database manager. Components can be deployed on different servers in a network and communicate with each other for needed services. A component runs within a context called a container. Examples of containers include pages on a Web site, Web browsers, and word processors.


  • Beowulf is an approach to building a supercomputer as a cluster of commodity off-the-shelf personal computers, interconnected with a local area network technology like Ethernet, and running programs written for parallel processing . The Beowulf idea is said to enable the average university computer science department or small research company to build its own small supercomputer that can operate in the gigaflop (billions of operations per second) range. In addition to possible cost savings, building your own supercomputer is said to be a learning investment and make you less dependent in the future on particular hardware and software vendors. As off-the-shelf technology evolves, a Beowulf can be upgraded to take advantage of it.
  • The original Beowulf cluster was developed in 1994 at the Center of Excellence in Space Data and Information Sciences (CESDIS), a contractor to the US National Aeronautics and Space Administration (NASA) at the Goddard Space Flight Center in Greenbelt, Maryland. Thomas Sterling and Don Becker built a cluster computer that consisted of 16 Intel DX4 processors connected by channel-bonded 10 Mbps Ethernet. Their success led to the Beowulf Project, which fosters the development of similar commodity off-the-shelf (COTS ) clusters. A number have been developed in universities and research groups, ranging from the original 16-processor Beowulf to Avalon, a cluster of 140 Alpha processors built by the Los Alamos National Laboratory. A more typical smaller cluster might have 16 200-MHz (or faster) Intel P6 processors connected by Fast Ethernet and a Fast Ethernet switch.
  • As a way to lower cost and increase vendor independency, Beowulf developers often choose the Linux operating system and use standard message passing protocol s between the computers within the cluster. A Beowulf cluster is placed in the taxonomy of parallel computing as somewhere below a massively parallel processor (MPP) and a network of workstations (NOW) that is clustered for the purpose of load balancing.

Berkeley Software Distribution - BSD:

  • Berkeley Software Distribution (BSD) refers to the particular version of the UNIX operating system that was developed at and distributed from the University of California at Berkeley. "BSD" is customarily preceded by a number indicating the particular distribution level of the BSD system (for example, "4.3 BSD"). BSD UNIX has been popular and many commercial implementations of UNIX systems are based on or include some BSD code.

BGP - Border Gateway Protocol:

  • An Internet protocol that enables groups of routers (called autonomous systems) to share routing information so that efficient, loop-free routes can be established. BGP is commonly used within and between Internet Service Providers (ISPs). The protocol is defined in RFC 1771.

Binary Digit - Bit:

  • A Binary Digit or bit is the smallest unit of data in a computer. A bit has a single binary value, either 0 or 1. Although computers usually provide instructions that can test and manipulate bits, they generally are designed to store data and execute instructions in bit multiples called bytes. In most computer systems, there are eight bits in a byte . The value of a bit is usually stored as either above or below a designated level of electrical charge in a single capacitor within a memory device.
  • Half a byte (four bits) is called a nibble. In some systems, the term octet is used for an eight-bit unit instead of byte. In many systems, four eight-bit bytes or octets form a 32-bit word . In such systems, instruction lengths are sometimes expressed as full-word (32 bits in length) or half-word (16 bits in length). In telecommunication, the bit rate is the number of bits that are transmitted in a given time period, usually a second.

Binary Runtime Environment for Wireless - BREW:

  • Binary Runtime Environment for Wireless (BREW) is Qualcomm's open source application development platform for wireless devices equipped for code division multiple access (CDMA ) technology. BREW makes it possible for developers to create portable applications that will work on any handsets equipped with CDMA chipset s. Because BREW runs in between the application and the chip operating system software, the application can use the device's functionality without the developer needing to code to the system interface or even having to understand wireless applications. Users can download applications - such as text chat, enhanced e-mail, location positioning, games (both online and offline), and Internet radio - from carrier networks to any BREW-enabled phone.
  • BREW is competing for wireless software market share with J2ME (Java 2 Micro Edition), a similar platform from Sun Microsystems. The initial version of BREW is solely for CDMA networks; later versions could be enabled for time division multiple access (TDMA) and Global System for Mobile Communication (GSM) networks.


  • In computer programming, to bind is to make an association between two or more programming objects or value items for some scope of time and place. Here are some usages:
  • 1) In general, when a program is compiled, to bind is to substitute a real for a variable value in the program or to ensure that additional programming will be loaded into storage along with the compiled program.
  • 2) When a server application is started, it issues a bind request to TCP/IP to indicate that it is ready to listen to (receive) client application requests from the Internet that are associated with a specified IP address. (Using the C programming language, the request is specified in a bind( ) function request.)
  • 3) In IBM's Systems Network Architecture (SNA), to bind is to set up a session between two logical units (LUs) or network end points prior to communicating.
  • 4) In using Remote Procedure Call (RPC ), to bind is to locate the remote server application to which a client application can make requests. This is often done by accessing a centrally-maintained directory of the names of accessible network server applications.
  • 5) An earlier program that did "binding" so that different programs that called each other knew each other's addresses in memory was called a linkage editor.

BIOS - Basic Input Output System:

  • See Basic Input Output System.

Bipolar 8-zero Substitution:

  • Bipolar 8-zero Substitution, also called binary 8-zero substitution, clear channel, and clear 64) (B8ZS) is an encoding method used on T1 circuits that inserts two successive ones of the same voltage - referred to as a bipolar violation - into a signal whenever eight consecutive zeros are transmitted. The device receiving the signal interprets the bipolar violation as a timing mark, which keeps the transmitting and receiving devices synchronized. Ordinarily, when successive ones are transmitted, one has a positive voltage and the other has a negative voltage.
  • B8ZS is based on an older encoding method called alternate mark inversion (AMI). AMI is used with Dataphone Digital Service, the oldest data service still in use that uses 64 Kbps channel s. AMI, however, requires the use of 8 Kbps of the 64 Kbps of each channel to maintain synchronization. In a T1 circuit, there are 24 channels. This loss adds up to 192 Kbps, which means that in reality only 56 Kbps is available for data transmission. B8ZS uses bipolar violations to synchronize devices, a solution that does not require the use of extra bits, which means a T1 circuit using B8ZS can use the full 64 Kbps for each channel for data. B8ZS is not compatible with older AMI equipment.
  • T1 technology is used in the United States and Japan. In Europe, a comparable technology called E1 provides 32 channels instead of 24 and uses an encoding scheme called high-density bipolar 3 (HDB3) instead of B8ZS.

Bit - Binary Digit:

  • See Binary Digit.

Blade Server:

  • A blade server is a thin, modular electronic circuit board, containing one, two, or more microprocessor s and memory, that is intended for a single, dedicated application (such as serving Web pages) and that can be easily inserted into a space-saving rack with many similar servers. One product offering, for example, makes it possible to install up to 280 blade server modules vertically in multiple racks or rows of a single floor-standing cabinet. Blade servers, which share a common high-speed bus, are designed to create less heat and thus save energy costs as well as space. Large data centers and Internet service providers (ISPs) that host Web sites are among companies most likely to buy blade servers.
  • A blade server is sometimes referred to as a high-density server and is typically used in a clustering of servers that are dedicated to a single task, such as:
  • * File sharing
  • * Web page serving and caching
  • * SSL encrypting of Web communication
  • * transcoding of Web page content for smaller displays
  • * Streaming audio and video content
  • Like most clustering applications, blade servers can also be managed to include load balancing and failover capabilities. A blade server usually comes with an operating system and the application program to which it is dedicated already on the board. Individual blade servers are usually hot-pluggable and come in various heights, including 5.25 inches (the 3U model), 1.75 inches (1U), and possibly "sub-U" sizes. (A U is a standard measure of vertical height in an equipment cabinet and is equal to 1.75 inches.)

BNC - Bayonet Neil-Concelman, or British Naval Connector:

  • A BNC (Bayonet Neil-Concelman, or sometimes British Naval Connector) connector is used to connect a computer to a coaxial cable in a 10BASE-2 Ethernet network. 10BASE-2 is a 10 MHz baseband network on a cable extending up to 185 meters - the 2 is a rounding up to 200 meters - without a repeater cable. 10BASE-2 Ethernets are also known as "Thinnet ", "thin Ethernet", or "cheapernets". The wiring in this type of Ethernet is thin, 50 ohm, baseband coaxial cable. The BNC connector in particular is generally easier to install and less expensive than other coaxial connectors.
  • A BNC male connector has a pin that connects to the primary conducting wire and then is locked in place with an outer ring that turns into locked position.
  • Different sources offer different meanings for the letters BNC. However, our most knowledgable source indicates that the B stands for a bayonet-type connection (as in the way a bayonet attaches to a rifle) and the NC for the inventors of the connector, Neil and Concelman.

BOOTP - Bootstrap Protocol:

  • See Bootstrap Protocol.

Bootstrap Protocol - BOOTP:

  • Bootstrap Protocol (BOOTP) is a protocol that lets a network user be automatically configured (receive an IP address) and have an operating system booted (initiated) without user involvement. The BOOTP server , managed by a network administrator, automatically assigns the IP address from a pool of addresses for a certain duration of time.
  • BOOTP is the basis for a more advanced network manager protocol, the Dynamic Host Configuration Protocol (DHCP).

Bourne Shell:

  • The Bourne shell is the original UNIX shell (command execution program, often called a command interpreter) that was developed at AT&T. Named for its developer, Stephen Bourne, the Bourne shell is also known by its program name, sh. The shell prompt (character displayed to indicate readiness for input) used is the $ symbol. The Bourne shell family includes the Bourne, Korn shell, bash, and zsh shells.
  • Bourne Again Shell (bash) is the free version of the Bourne shell distributed with Linux systems. Bash is similar to the original, but has added features such as command line editing. Its name is sometimes spelled as Bourne Again SHell, the capitalized Hell referring to the difficulty some people have with it.
  • Zsh was developed by Paul Falstad as a replacement for both the Bourne and C shell . It incorporates features of all the other shells (such as file name completion and a history mechanism) as well as new capabilities. Zsh is considered similar to the Korn shell. Falstad intended to create in zsh a shell that would do whatever a programmer might reasonably hope it would do. Zsh is popular with advanced users.
  • Along with the Korn shell and the C shell, the Bourne shell remains among the three most widely used and is included with all UNIX systems. The Bourne shell is often considered the best shell for developing scripts.

BREW - Binary Runtime Environment for Wireless:

  • See Binary Runtime Environment for Wireless.


  • In telecommunication networks, a bridge is a product that connects a local area network (LAN) to another local area network that uses the same protocol (for example, Ethernet or token ring ). You can envision a bridge as being a device that decides whether a message from you to someone else is going to the local area network in your building or to someone on the local area network in the building across the street. A bridge examines each message on a LAN, "passing" those known to be within the same LAN, and forwarding those known to be on the other interconnected LAN (or LANs).
  • In bridging networks, computer or node addresses have no specific relationship to location. For this reason, messages are sent out to every address on the network and accepted only by the intended destination node. Bridges learn which addresses are on which network and develop a learning table so that subsequent messages can be forwarded to the right network.
  • Bridging networks are generally always interconnected local area networks since broadcasting every message to all possible destinations would flood a larger network with unnecessary traffic. For this reason, router networks such as the Internet use a scheme that assigns addresses to nodes so that a message or packet can be forwarded only in one general direction rather than forwarded in all directions.
  • A bridge works at the data-link (physical network) level of a network, copying a data frame from one network to the next network along the communications path. A bridge is sometimes combined with a router in a product called a brouter.

British Naval Connector - BNC:

  • See BNC.


  • In general, broadband refers to telecommunication in which a wide band of frequencies is available to transmit information. Because a wide band of frequencies is available, information can be multiplexed and sent on many different frequencies or channels within the band concurrently, allowing more information to be transmitted in a given amount of time (much as more lanes on a highway allow more cars to travel on it at the same time). Related terms are wideband (a synonym), baseband (a one-channel band), and narrowband (sometimes meaning just wide enough to carry voice, or simply "not broadband," and sometimes meaning specifically between 50 cps and 64 Kpbs).
  • Various definers of broadband have assigned a minimum data rate to the term. Here are a few:
  • * Newton's Telecom Dictionary: "...greater than a voice grade line of 3 KHz...some say [it should be at least] 20 KHz."
  • * Jupiter Communications: at least 256 Kbps.
  • * IBM Dictionary of Computing: A broadband channel is "6 MHz wide."
  • It is generally agreed that Digital Subscriber Line (DSL) and cable TV are broadband services in the downstream direction.


  • A browser is an application program that provides a way to look at and interact with all the information on the World Wide Web. The word "browser" seems to have originated prior to the Web as a generic term for user interfaces that let you browse (navigate through and read) text files online. By the time the first Web browser with a graphical user interface was generally available (Mosaic, in 1993), the term seemed to apply to Web content, too. Technically, a Web browser is a client program that uses the Hypertext Transfer Protocol (HTTP) to make requests of Web servers throughout the Internet on behalf of the browser user. A commercial version of the original browser, Mosaic, is in use. Many of the user interface features in Mosaic, however, went into the first widely-used browser, Netscape Navigator. Microsoft followed with its Microsoft Internet Explorer . Today, these two browsers are the only two browsers that the vast majority of Internet users are aware of. Although the online services, such as America Online, originally had their own browsers, virtually all now offer the Netscape or Microsoft browser. Lynx is a text-only browser for UNIX shell and VMS users. Another recently offered and well-regarded browser is Opera.
  • While some browsers also support e-mail (indirectly through e-mail Web sites) and the File Transfer Protocol (FTP), a Web browser is not required for those Internet protocols and more specialized client programs are more popular.

Brute Force:

  • Brute force (also known as brute force cracking) is a trial and error method used by application programs to decode encrypted data such as passwords or Data Encryption Standard (DES ) keys, through exhaustive effort (using brute force) rather than employing intellectual strategies. Just as a criminal might break into, or "crack" a safe by trying many possible combinations, a brute force cracking application proceeds through all possible combinations of legal characters in sequence. Brute force is considered to be an infallible, although time-consuming, approach.
  • Crackers are sometimes used in an organization to test network security, although their more common use is for malicious attacks. Some variations, such as L0phtcrack from L0pht Heavy Industries, start by making assumptions, based on knowledge of common or organization-centered practices and then apply brute force to crack the rest of the data. L0phtcrack uses brute force to crack Windows NT passwords from a workstation. PC Magazine reported that a system administrator who used the program from a Windows 95 terminal with no administrative privileges, was able to uncover 85 percent of office passwords within twenty minutes.

BSD - Berkeley Software Distribution:

  • See Berkeley Software Distribution


  • The term "Boolean," often encountered when doing searches on the Web (and sometimes spelled "boolean"), refers to a system of logical thought developed by the English mathematician and computer pioneer, George Boole (1815-64). In Boolean searching, an "and" operator between two words or other values (for example, "pear AND apple") means one is searching for documents containing both of the words or values, not just one of them. An "or" operator between two words or other values (for example, "pear OR apple") means one is searching for documents containing either of the words.
  • In computer operation with binary values, Boolean logic can be used to describe electromagnetically charged memory locations or circuit states that are either charged (1 or true) or not charged (0 or false). The computer can use an AND gate or an OR gate operation to obtain a result that can be used for further processing. The following table shows the results from applying AND and OR operations to two compared states:
  • 0 AND 0 = 0, 1 AND 0 = 0, 1 AND 1 = 1, 0 OR 0 = 0, 0 OR 1 = 1, 1 OR 1 = 1
  • For a summary of logic operations in computers, see logic gate.


  • In most computer systems, a byte is a unit of data that is eight binary digits long. A byte is the unit most computers use to represent a character such as a letter, number, or typographic symbol (for example, "g", "5", or "?"). A byte can also hold a string of bits that need to be used in some larger unit for application purposes (for example, the stream of bits that constitute a visual image for a program that displays images or the string of bits that constitutes the machine code of a computer program).
  • In some computer systems, four bytes constitute a word , a unit that a computer processor can be designed to handle efficiently as it reads and processes each instruction. Some computer processors can handle two-byte or single-byte instructions.
  • A byte is abbreviated with a "B". (A bit is abbreviated with a small "b".) Computer storage is usually measured in byte multiples. For example, an 820 MB hard drive holds a nominal 820 million bytes - or megabytes - of data. Byte multiples are based on powers of 2 and commonly expressed as a "rounded off" decimal number. For example, one megabyte ("one million bytes") is actually 1,048,576 (decimal) bytes. (Confusingly, however, some hard disk manufacturers and dictionary sources state that bytes for computer storage should be calculated as powers of 10 so that a megabyte really would be one million decimal bytes.)
  • Some language scripts require two bytes to represent a character. These are called double-byte character sets (DBCS). According to Fred Brooks, an early hardware architect for IBM, project manager for the OS/360 operating system, and author of The Mythical Man-Month, Dr. Werner Buchholz originated the term byte in 1956 when working on IBM's STRETCH computer.


  • Bytecode is computer object code that is processed by a program, usually referred to as a virtual machine, rather than by the "real" computer machine, the hardware processor. The virtual machine converts each generalized machine instruction into a specific machine instruction or instructions that this computer's processor will understand. Bytecode is the result of compiling source code written in a language that supports this approach. Most computer languages, such as C and C++, require a separate compiler for each computer platform - that is, for each computer operating system and the hardware set of instructions that it is built on. Windows and the Intel line of microprocessor architectures are one platform; Apple and the PowerPC processors are another. Using a language that comes with a virtual machine for each platform, your source language statements need to be compiled only once and will then run on any platform.
  • The best-known language today that uses the bytecode and virtual machine approach is Java. The LISP language, used in artificial intelligence applications, is an earlier language that compiled bytecode. Other languages that use bytecode or a similar approach include Icon and Prolog.
  • Rather than being interpreted one instruction at a time, Java bytecode can be recompiled at each particular system platform by a just-in-time compiler. Usually, this will enable the Java program to run faster. In Java, bytecode is contained in a binary file with a .CLASS suffix.


  • Bytepile, a word created from the merger of "byte" and "pile" and conceived of in 2002 for the purpose of naming, at that time, the new Since the business model at is driven around data storage and web hosting, it was only natural that a large heap of data is in some sense metaphorically the same as a large heap of sand a.k.a. sand pile, hence the creation of the word bytepile.


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