Common Computer Jargon

GLOSSARY – EXPLANATION OF I.T. LANGUAGE

Authentication - Security feature that determines a user's identity and legitimacy.

Bandwidth -The range of transmission frequencies that a network can use. The greater the bandwidth, the greater the amount of data that a cable can carry. Bandwidth is measured in bits per second (bps) for digital signals, or in hertz (Hz) for analog signals.

BUS - 1) A collection of wires through which data is transmitted from one part of a computer to another. You can think of a bus as a highway on which data travels within a computer. When used in reference to personal computers, the term bus usually refers to internal bus. This is a bus that connects all the internal computer components to the CPU and main memory. There's also an expansion bus that enables expansion boards to access the CPU and memory.

All buses consist of two parts -- an address bus and a data bus. The data bus transfers actual data whereas the address bus transfers information about where the data should go.

The size of a bus, known as its width, is important because it determines how much data can be transmitted at one time. For example, a 16-bit bus can transmit 16 bits of data, whereas a 32-bit bus can transmit 32 bits of data.

Every bus has a clock speed measured in MHz. A fast bus allows data to be transferred faster, which makes applications run faster. On PCs, the old ISA bus is being replaced by faster buses such as PCI.

Nearly all PCs made today include a local bus for data that requires especially fast transfer speeds, such as video data. The local bus is a high-speed pathway that connects directly to the processor.

Several different types of buses are used on Apple Macintosh computers. Older Macs use a bus called NuBus, but newer ones use PCI.

(2) In networking, a bus is a central cable that connects all devices on a local-area network (LAN). It is also called the backbone.

CPU - Abbreviation of central processing unit, and pronounced as separate letters. The CPU is the brains of the computer. Sometimes referred to simply as the processor or central processor, the CPU is where most calculations take place. In terms of computing power, the CPU is the most important element of a computer system.

On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single chip called a microprocessor.

Two typical components of a CPU are:

The arithmetic logic unit (ALU), which performs arithmetic and logical operations.
The control unit (CU), which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.

Dedicated Link - An exclusive port dedicated for a dial-up IP account.

Dial-up Link - Also called a switched line, a dial-up link is a low-cost connection to the Internet through a nondedicated communications line.

DNS - Acronym for Domain Name System. The distributed naming service used on the Internet. For example, ftp.novell.de is the name of a Novell server in Germany that contains patches for Novell products.

DNS Server - A server that contains IP addressing information.

Domain - The highest subdivision of the Internet, which are usually by country or type of entity (for example, government or commercial). DNS organises groups of computers on the Internet through a hierarchy of domains.

Domain Name The complete domain name address, including the domain and the unique name of the organisation; for example, novell.com.

DSU - Acronym for data service unit. The side of the communications channel equipment connected to the bridge or router. It converts all incoming data into the proper format for transmission over the T1 or fractional T1 circuit.

Firewall A feature that protects a network connected to the Internet from being accessed by unauthorised users.

HARD DRIVE - The mechanism that reads and writes data on a hard disk. Hard disk drives (HDDs) for PCs generally have seek times of about 12 milliseconds or less. Many disk drives improve their performance through a technique called caching.

There are several interface standards for passing data between a hard disk and a computer. The most common are IDE and SCSI.

Hard disk drives are sometimes called Winchester drives, Winchester being the name of one of the first popular hard disk drive technologies developed by IBM in 1973.

IPX - Acronym for Internetwork Packet Exchange. Default protocol used by NetWare systems to route information packets over a local or wide area network. IPX has the same function as TCP/IP.

ISDN - Acronym for Integrated Services Digital Network. A new telecommunications standard being introduced by telephone companies. It enables the transmission of voice, data, and certain images over telephone lines through end-to-end digital circuits.

LAN - LOCAL-AREA NETWORK- A computer network that spans a relatively small area. Most LANs are confined to a single building or group of buildings. However, one LAN can be connected to other LANs over any distance via telephone lines and radio waves. A system of LANs connected in this way is called a wide-area network (WAN).

Most LANs connect workstations and personal computers. Each node (individual computer ) in a LAN has its own CPU with which it executes programs, but it also is able to access data and devices anywhere on the LAN. This means that many users can share expensive devices, such as laser printers, as well as data. Users can also use the LAN to communicate with each other, by sending e-mail or engaging in chat sessions.

There are many different types of LANs Ethernets being the most common for PCs. Most Apple Macintosh networks are based on Apple's AppleTalk network system, which is built into Macintosh computers.

Local Area Network - LANs are capable of transmitting data at very fast rates, much faster than data can be transmitted over a telephone line; but the distances are limited, and there is also a limit on the number of computers that can be attached to a single LAN.

The following characteristics differentiate one LAN from another:

1. Topology - The geometric arrangement of devices on the network. For example, devices can be arranged in a ring or in a straight line.
2. Protocols - The rules and encoding specifications for sending data. The protocols also determine whether the network uses a peer-to-peer or client/server architecture.
3. Media - Devices can be connected by twisted-pair wire, coaxial cables, or fiber optic cables. Some networks do without connecting media altogether, communicating instead via radio waves.

MOTHERBOARD - The main circuit board of a microcomputer. The motherboard contains the connectors for attaching additional boards. Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parallel ports, expansion slots, and all the controllers required to control standard peripheral devices, such as the display screen, keyboard, and disk drive. Collectively, all these chips that reside on the motherboard are known as the motherboard's chipset.

On most PCs, it is possible to add memory chips directly to the motherboard. You may also be able to upgrade to a faster PC by replacing the CPU chip. To add additional core features, you may need to replace the motherboard entirely.

Motherboard is sometimes abbreviated as mobo.

MHZ - Abbreviation for megahertz. One MHz represents one million cycles per second. The speed of microprocessors, called the clock speed, is measured in megahertz. For example, a microprocessor that runs at 200 MHz executes 200 million cycles per second. Each computer instruction requires a fixed number of cycles, so the clock speed determines how many instructions per second the microprocessor can execute. To a large degree, this controls how powerful the microprocessor is. Another chief factor in determining a microprocessor's power is its data width (that is, how many bits it can manipulate at one time).

In addition to microprocessors, the speeds of buses and interfaces are also measured in MHz.

NSFnet - A network that serves as part of the current Internet backbone funded by the National Science Foundation.

Point of Presence A POP is the regional hub used by an Internet Service Provider to connect networks.

RAM ( MEMORY ) - There are two basic types of RAM. Namely Dynamic RAM (DRAM) and Static RAM (SRAM)

The two types differ in the technology they use to hold data, dynamic RAM being the more common type. Dynamic RAM needs to be refreshed thousands of times per second. Static RAM does not need to be refreshed, which makes it faster; but it is also more expensive than dynamic RAM. Both types of RAM are volatile, meaning that they lose their contents when the power is turned off.

In common usage, the term RAM is synonymous with main memory, the memory available to programs. For example, a computer with 8M RAM has approximately 8 million bytes of memory that programs can use. In contrast, ROM (read-only memory) refers to special memory used to store programs that boot the computer and perform diagnostics. Most personal computers have a small amount of ROM (a few thousand bytes). In fact, both types of memory (ROM and RAM) allow random access. To be precise, therefore, RAM should be referred to as read/write RAM and ROM as read-only RAM.

Server A computer set up to distribute services or resources. It provides access to information from "clients", or requesting computers.

SMTP - Acronym for Simple Mail Transfer Protocol. The standard Internet protocol for sending and receiving e-mail.

TCP/IP - Acronym for Transmission Control Protocol/Internet Protocol. Default protocol used by UNIX systems to route information packets over a local or wide area network. The standard protocol upon which the Internet is based.

TWAIN - Defines a standard software protocol and application programming interface for communication between software applications and image acquisition devices. Most PC scanners include a TWAIN driver, which allows images to be captured directly into many popular applications. TWAIN is not actually an acronym (Technology Without An Interesting Acronym).

UNIX - Standard operating system which runs on servers and minicomputers today. Examples of UNIX include HP/UX, IBM AIX*, Sun Microsystems Solaris* and SCO* UNIX.

USB Variations

• USB 1x - The original USB 1.0 standard offered data rates of 1.5 Mbps. The USB 1.1 standard followed with two data rates: 12 Mbps for devices such as disk drives that need high-speed throughput and 1.5 Mbps for devices such as joysticks that need much less bandwidth.
• USB 2x - USB 2.0, also called Hi-Speed USB 2.0 It increased the data transfer rate for PC to USB device to 480 Mbps, which is 40 times faster than the USB 1.1 specification. With the increased bandwidth, high throughput peripherals such as digital cameras, CD burners and video equipment could now be connected with USB. It also allowed for multiple high-speed devices to run simultaneously. Another important feature of USB 2.0 is that it supports Windows XP through Windows update.
• USB OTG - USB On-the-Go (OTG) addresses the need for devices to communicate directly for mobile connectivity. USB OTG allows consumers to connect mobile devices without a PC. For example, USB OTG lets consumers plug their digital camera directly into a compliant printer and print directly from the camera, removing the need to go through the computer. Similarly, a PDA keyboard with a USB OTG interface can communicatea with any brand PDA that has a USB OTG interface.
  USB-OTG also provides limited host capability to communicate with selected other USB peripherals, a small USB connector to fit the mobile form factor and low power features to preserve battery life. USB OTG is a supplement to the USB 2.0 specification.
• Types of USB Connectors - Currently, there are four types of USB connectors: Type A, Type B, mini-A and mini-B and are supported by the different USB specifications (USB 1, USB 2 and USB-OTG).
• USB A (Host) - Often referred to as the downstream connector, the Type A USB connector is rectangular in shape and is the one you use to plug into the CPU or USB hub.
• USB B (Device) - Also called the upstream connector, the Type B USB connector is more box-shaped and is the end that attaches directly to the device (such as a printer or digital camera).
• USB 1.1 specifies the Type A and Type B.
• Mini-B - The USB 2.0 connector was too large for many of the new handheld devices, such as PDAs and cell phones. The mini-B was introduced to enable consumers to take advantage of USB PC connectivity for these smaller devices.
• USB 2.0 specifies the Type A, Type B and mini-B.
• Mini-A - With the need to connect mobile devices without the aid of a computer, the mini-A port was designed to connect the new generation of smaller mobile devices.
• USB OTG specifies the mini-A.
• Certified Wireless USB - With an estimated 2 billion plus USB connected devices in the world and a growing interest in wireless computing, it's no surprise that development has turned to wireless USB. The USB Implementers Forum has introduced Certified Wireless USB the newest extension to the USB technology. Wireless USB applies wireless technology to existing USB standards to enable wireless consumers to still use USB devices without the mess of wires and worry of cords. Still in its infancy, the Wireless USB specifications were made available to the public only in May 2005.

WAN - Acronym for wide area network. A physical communications network that operates across large geographical distances.

World Wide Web - A hypermedia-based system for organising information on the Internet.

X.25 - A standard that describes how data is handled in and how computers can access a packet-switched network.