Appendix Glossary P

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 - P

Packet - A unit of transmitted information containing specific protocols and codes that allows precise sending and receiving of information from one networked node to another.

Packet Switching - The method used to send information over a network. Each packet has the address of the sender as well as the destination address. This allows information to intermingle with other packets of data, without being lost or misdirected, while making it's journey over the network.

PageMaker - A page layout program produced by Adobe Systems for both Windows and Macintosh users. PageMaker has been around since the early days of desktop publishing and still has a broad and very loyal following. So loyal are its users that the mere mention of its competitor, QuarkXPress, in some circles is enough to get you some perfectly-kerned hate mail from PageMaker fans.

PageMill - Pagemill is the name of the application that is available from Adobe to provide users with a graphical interface for the creation of web pages. This type of program is commonly referred to as an "HTML editor" because its job is to generate HTML files based on the commands executed in the page layout interface available to the user. Other HTML editing packages include Microsoft FrontPage and Macromedia Dreamweaver. The alternative to using a program like this to create web pages is to either use a text editor and enter the HTML codes directly, or get someone else to make your web pages for you (someone else who will probably use an HTML editor and tell you he or she did it by hand).

Pagination - The assignment of numbers to the pages in a document. Logically, one would think that one number simply followed another, but in word processing jobs, allowances can be made for objects such as charts and blank pages, which the author might want excluded from the logical numbering sequence. Word processing programs also automatically divide text into single pages. Without this function a document would appear to be one continuous page.

Palette - One of a set of tools included in graphics and paint applications. The palette is a selection of colours, usually displayed in small boxes. The user can select the desired colour, and click OK to apply it.

Palmtop - A computer small enough to fit in the user's hand. Primarily used as personal organisers, they provide users with the ability to store names and addresses, play games, access the Internet, and use a calculator.

Parallel Port - A parallel port is a common interface to (faster) devices such as printers, and some video capture devices.

Parallel Processing - The simultaneous use of more than one microprocessor to run a program, allowing for faster execution.

Parameter - An identifying feature, value, or characteristic. In programming, a parameter represents a boundary or value, which might trigger a function or action.

Parity - Data integrity checking that adds a single bit to each byte of data. The parity bit is used to detect errors in the other 8 bits.

Parse - To divide, analyse, and categorise individual components of language into small units so they can be utilised usefully in computer programming.

Partition - A portion of a hard disk dedicated to a particular operating system or application and accessed as a single logical volume.

Pascal - A high level programming language based on Algorithmic Language (AL GOL) developed in the early 1970's by Niklaus Wirth. The language was named after the seventeenth century mathematician Blaise Pascal who built one of the first mechanical adding machines. Pascal is noted for its highly systematic and methodical structure, making it a popular teaching language.

Passive Matrix - A low resolution liquid crystal flat-panel display used for computer monitors. Although the display quality is not quite up to par with the activematrix display screens, the significant difference in the cost of the passive matrix has caused it to remain popular.

Paste - An efficient way to insert a single letter, word, an entire block of text, or an image from one location within a document or file, to the same or another document or file. To paste, means to place the material, into a document.

Path - In DOS and Windows, the series of directories where an operating system searches for executable files called up by a user.

Pathname - This is the full, exact name of a file or directory on a disk. It includes the drive letter, a colon, a directory name, and a filename. Being EXACTING is the key to locating any file on a system.

PC - This means Personal Computer. Before the first IBM PC, personal computers were called "microcomputers" after the microprocessor. Now all personal computers, even non-DOS computers are called PCs.

PC Card - (PCMCIA: Personal Computer Memory Card International Association) A standard that allows interchangeability of various computing components on the same connector. The PCMCIA standard supports input-output devices, including memory, fax/modem, SCSI, and networking products. Communication cards the size of a credit card that fit into the small PC Card slot of portable computers or other networking devices.

PC100 A computer industry designation for a special type of SDRAM (Synchronous Dynamic Random Access Memory) designed for use in computers with a 100 MHz bus. If a system includes a motherboard designated as "Super7" or "BX," be sure that includes PC100 SDRAM (or faster) for maximum reliability and performance.

PC133 Computers designed for use with a 133 MHz FSB require this faster (and consequently more expensive) memory. PC133 memory can also be used with slower 100 

PC99  A standard computer specification set out by Intel, Microsoft and other computer industry manufacturers. The PC99 spec calls for the elimination of often-troublesome ISA slots, minimum processor speeds for desktop systems of 300 MHz, and a minimum 64 MB of RAM. The required absence of ISA slots in the spec means that few of today's motherboards are fully PC99 compliant.

PCB - (Printed Circuit Board) - Generally flat, multi-layer boards made of fibreglass with electrical traces. The surface and sublayers use copper traces to provide electrical connections for chips and other components. Examples of PCBs include: motherboards, SIMMs, and credit card memory.

PCDOS - This is the original IBM version of DOS. You can run PC-DOS on non-IBM computers.

PCI - (Peripheral Component Interconnect)- A peripheral bus that can send 32 or 64 bits of data simultaneously. PCI offers plug-and-play capability. PCI is an acronym for "Peripheral Component Interconnect," this style of expansion slot is easier to configure than the older ISA variety, and generally provides better performance. For fewer computer hassles, try to avoid ISA add-on cards for sound cards and other interfaces and go for PCI cards instead. On this note, look for a system with plenty of unused PCI slots.

PCMCIA - (Personal Computer Memory Card International Association) an international standards body and trade association with over 500 member companies founded in 1989 to establish standards for Integrated Circuit cards and to promote interchangeability among mobile computers where durability, low power, and small size were critical. Among the standards a card needs for PCMCIA compliance are uniform thickness and size.

PDA - (Personal Digital Assistant) a generic term for any number of electronic computing or communications devices that are able to act as cellular phones, fax senders or personal organisers. Although somewhat expensive, PDAs are becoming more sophisticated and easier to use.

PDF - "Portable Document Format" PDF is the file format used in Adobe's electronic document distribution model. The program that is responsible for saving and reading files in the PDF is Adobe Acrobat. Using Acrobat, the creator of a document can export content created in a page layout or graphic generation program in the PDF. This document can then be viewed and printed by anyone who has a copy of the Acrobat Reader software, which is available free of charge from Adobe. You just have to love free stuff.

Peer To Peer - A network computing system in which all computers are treated as equals on the network. Individual computers may share hard drives, CD-ROM drives, and other storage devices with the other computers on the network. This is different than a client/server set-up in which most of the computers (clients) tend to share resources from one main computer (the server).

Pentium - Refers to a number of microprocessors manufactured by Intel corporation, including the first in the line introduced in 1993, the Pentium microprocessor, the Pentium Pro, the Pentium II, and most recently, the Pentium III. With the introduction of each successive Pentium product, processing efficiency, speed and power has dramatically increased.

Pentium II - Intel's successor to the "Pentium" processor, requires a "Slot 1" motherboard a different type of design than that used by the original Pentium or AMD chip designs. Older Pentium II processors supported a 66 megahertz "bus" (external clock) speed. Newer models (starting with the Pentium II/350) support a 100 megahertz bus. Slot 1 motherboards that support this faster bus are typically known as "BX" motherboards. Older "LX" motherboards officially support 66 MHz bus speeds only.

Pentium III - An Intel "Slot 1" family processor that includes 70 multimedia instructions (known as SSE, or Streaming SIMD extensions) not found in the Pentium II. Newer Pentium IIIE processors are also known as "Coppermine."

Pentium IIPE - The "PE" stands for "Performance Enhanced" in the new Pentium II and Celeron processors for portable computers announced by Intel on Jan. 25th, 1999. Like the PPGA versions of the Celeron released in Jan. 1999, these chips have the L2 cache integrated on the main processor, instead of being separate, as they are in the "Slot 1" versions of these processors. Integrating the cache improves performance and allows the chip package to be smaller.

Performance - A measure of the speed of the drive during normal operation. Factors affecting performance are seek times, transfer rate, and command overhead.

Peripheral - A device added to a system as a complement to the basic CPU, such as a disk drive, tape drive, or printer. This refers to any device attached to the outside of the computer.

Perl - A popular programming language developed by Larry Wall primarily for processing CGI scripts.

PGP - (Pretty Good Privacy) a free security application developed by Phillip Zimmerman that allows users to email files anywhere in the world. The program includes a feature that lets the sender know the files were received and that they actually came from the sender. Additionally, PGP Security offers a complete line of network security software, available from Network Associates of Santa Clara California.

Photo CD - Photo CD is a proprietary CD-ROM format created by Kodak. The technology was introduced to provide a cost-effective way to get images from 35 millimetre photographic film to digitised files on a CD-ROM. The act of creating a Photo CD is a combination of photofinishing and CD authoring. It requires the use of a specialised hardware/software solution that is not part of the standard CD-ROM creation process. Despite what the name may suggest, a Photo CD is not simply any CD with photos on it. By the same token, the act of putting digitised photos onto a CD-ROM does not necessarily result in a Photo CD.

Photo Scanner - An optical scanner that specialises in scanning photos. Photo scanners usually offer better resolution than conventional scanners.

Phreaking - Similar to hacking, only the phreaker's goal is to access a phone system for the purpose of making free calls.

Physical Format - The actual physical layout of cylinders, tracks, and sectors on a disk drive.

PICT - PICT is an image file format that is used primarily for screen-oriented graphics (most commonly in a Macintosh environment). Despite the fact that the file architecture is capable of supporting the full content of very detailed graphic files, it is not used as a standard for laying out print documents.

PIF - (Program Information File) in DOS and Windows, a file that contains instructions on how to run a program other than DOS or Windows.

Ping - A process used to send data packets over a TCP/IP network to test whether the hardware and software is working properly. The ping program is available in the Windows operating system and is available in shareware forms for Macs.

Pipe - A connection between two software programs that acts as a shortcut in accessing data.

Pipeline Burst Cache - Cache that reduces wait states and accelerates memory access by using pipelining and bursting functions.

Pipelining - A technique in which memory loads the requested memory contents into a small cache composed of SRAM, then immediately begins fetching the next memory contents. This creates a two-stage pipeline, where data is read from or written to SRAM in one stage, and data is read from or written to memory in the other stage.

Piracy - The unauthorised duplication and/or use and distribution of a software program. Buying a program usually allows the user a limited license for its use on a single computer. In the past, software manufacturers tried to discourage piracy by copy-protecting their products. However, because US copyright laws allow a legitimate holder of a program to make a backup disk, measures such as owner registration have been used to discourage unauthorised use. Aside from being illegal, there are several other reasons for not using pirated software. Among them, the user gets no operating manual, no technical support, and runs the risk of introducing viruses into a computer by installing a bootlegged program.

Pixel - "Picture Element" Any image that is displayed from a digital file is made up of individual dots or "pixels." The pixel is the smallest unit of measurement in digital images, and the smaller the pixels, the finer the potential for detail. When it comes to pixels, bigger is definitely not better. The number of pixels contained in a given space (such as each inch or each centimetre) is defined by the resolution of an image. You can think of it as a "dot" of colour that is too small to be seen by itself. Hundreds of these dots viewed together make up the image you see on your screen. More pixels are better, because the screen can display more detailed images. Screen resolution is often expressed in pixels - 1024x768 means a screen displays 1024 pixels horizontally by 768 pixels vertically, for a total of 786,432 pixels.. So, when we say an image is 140 x 60 we mean the image is 140 pixels wide by 60 pixels high. Each pixel can be a different colour and in a different position. This creates the image that you see on the screen. The number of horizontal and vertical pixels determined the resolution of the graphic.

PKZIP - A PKZIP (or zip) file is a common means of compressing and distributing data on the Windows platform. Through the use of a small software CODEC (usually a shareware or freeware program), the ZIP format can make files a whole lot more compact. The Macintosh counterpart of the zip process would be to create and distribute Stuffit files, although there are programs that can read and write zip files on the Macintosh.

Plasma Display - A flat display monitor that uses ionised gas compressed between panels to produce images.

Plated Media - Disks that are covered with a hard metal alloy instead of an iron-oxide compound. Plated disks can store more data than their oxide-coated counterparts.

Platform - The type of operating system or hardware that make up a computer or computer system. These factors provide a particular environment for operation. The platform determines the parameters under which a system runs associated hardware and software. For example, software designed to run on a Macintosh, will not run on a PC and visa-versa. For Mac software, or hardware, to work in a PC environment, it would need to be cross-platformed.

Platter - A disk made of metal (or other rigid material) that is mounted inside a fixed disk drive. Most drives use more than one platter mounted on a single spindle (shaft) to provide more data storage surfaces in a smaller area. POH - Acronym for power on hours. The unit of measurement for mean time between failure (MTBF), expressed as the number of hours that the drive is powered on.

Plotter - A computer output device that draws images on paper using a pen. A plotter draws real lines rather than simulating them as a conventional printer would by producing a series of very close dots.

Plug and Play - An identifying standard in the PC market that assures the user that the product is as simple or automatic to install as possible; both hardware and software installation. Because this often does not work as well as claimed, it is also commonly known and "plug and pray."

Plug In - Add-ons for Web browsers. Plug-ins are typically very small files that sit innocently on the user's hard drive and do all sorts of neat things.

PNG - (Portable Network Graphics) a graphics file format similar to GIF that encodes images as bitmaps.

PNP - plug and play.

Pointer - A symbol displayed on a computer screen whose movement corresponds to that of the mouse. The pointer usually presents as an arrow, but may have other forms such as a hand or flashing I beam.

Point To Point Tunnelling Protocol - (PPTP) PPTP is a network protocol that allows users to establish via an IP-network (usually over the Internet, but also possible via Intranets) a secure connection by encapsulating inside the IP-packet an encrypted private protocol, which can be NetBEUI, IPX or TCP/IP. Microsoft has implemented PPTP as VPN, or Virtual Private Networking.

POP - A POP (Point of Presence) is the modem which the Internet user dials from their computer to gain access to the Internet.

POP3 - "Post Office Protocol 3" A communication protocol that is used to retrieve electronic mail from a Mail Server. Unless you are a mail administrator, the only time you are likely to run into this term is when you are setting up your e-mail client software. If you play your cards right, you may even be able to avoid it altogether by conning somebody else into configuring your e-mail program.

Port - Port has a number of different meanings in the world of computing. A hardware port is the exact spot on a computer that is used to connect individual devices to it. The modem port is for the modem; the mouse port handles the mouse; the RS-232 port is where you plug in your RS232 thingy, etc. The act of "porting" a piece of software means engineering it to run on a platform other the one for which it was created. A server port is the specific designation of a communication channel used by the server to ensure a secure data transfer to or from a client. Port also happens to be the type of red wine that system administrators often swig while configuring data ports.

Portable - When speaking of hardware, lightweight and easily transported such as a laptop or a handheld computer. When speaking of software, the ability to operate on more than one type of computer.

Portal - An entry point to the World Wide Web usually providing services such as email, search engines, news, weather, stock quotes, chat and message forums, and a number of additional benefits designed to attract users to the site. Such Websites encourage users to set the site as their homepage Many of the top search engines, in an effort it increase site traffic, have endeavoured to become all-purpose cyber-utilities, providing a user with many of the services the World Wide Web has to offer. Yahoo and MSN are common portals.

Portrait - A document with vertical orientation. In other words, the page is taller than it is wide. Portrait orientation is opposite of Landscape.

Post - The term for an original USENET or mailing list article. Used as a verb, to "post" means to submit an article for publication on USENET in one or more newsgroups or to one or more mailing list. If sent to more than one newsgroup or list the post is said to be"cross-posted". If the newsgroup is moderated, the moderator decides if the post will appear; otherwise the post appears automatically.

PostScript - A page definition language introduced by Adobe Systems to standardise the means through which documents are created and delivered to the printer or other output device. While PostScript may be the language that the printer is capable of understanding, it is a PostScript oriented program like Adobe Illustrator or QuarkXpress that does the job of translating user-specified layout instructions to the PostScript language. This is fortunate, because anyone who's ever tried to edit a page in raw PostScript would agree that it makes Finnegan's Wake look like a Beetle Bailey cartoon.

PowerPC - A computer containing a high-powered microprocessor. They were developed as part of a joint venture among IBM, Apple and Motorola in an effort to compete with Intel and Microsoft. The first of the PowerPCs was the Power Mac introduced in 1994.

Power Supply - Supplies the motherboard with 5v and the other devices with 12v. It powers the computer.

PPGA - (Plastic Pin Grid Array) Also known as Socket 370. A socket found on motherboards designed for Intel's low-cost PGA Socket 370 Celeron processors. PGA Celerons can also be used in Slot 1 motherboards, with the addition of a Socket 370-to-Slot 1 adapter card, such as the Abit "Slotket."

PPM - (pages per minute) the number of pages per minute a printer can produce. The standard applies to text only as printing graphics slows a printer significantly.

PPP - Point to Point protocol. A protocol that allows your computer to join the Internet via a modem. Each time you log in you are assigned a temporary IP address.

Printer - This is a device which attaches to the computer and prints information. This is necessary to give you a "hard copy" or printed output of the information on your files in the computer.

Printer Port - This is the connection at the back of the computer into which you plug the printer cable. This attaches the printer to the computer. The printer port is also called the parallel port.

Processor Direct Slot - (PDS) An adapter slot available on some Macintoshes that connects directly to the motherboard. In these computers, network interface cards connect to the PDS slot.

Program - This is the file which runs a program. It has the instructions for the computer. The programs are stored in files with extensions on them of .EXE, .BAT, .COM. To run the program you need only type the first part of the filename (leaving off the extension).

Programming Language - The instructions used in creating computer programs. There are a great number of programming languages in existence and no one language is suitable for writing all types of programs. The language a programmer uses to create an application will depend on the desired properties of the program. Some programming languages lend themselves to mathematical and analytical functions while others are better suited for creating business or data processing applications. The programming language field is wide and complex, encompassing a large number of disciplines.

PROM - Programmable Read-Only Memory (Written to once)

Prompt - It looks like this : C> or whatever other directory you may be in eg C:\GAMES> . It is at this point, where the cursor is blinking that you may type DOS commands to operate programs etc. If someone tells you to go to a DOS prompt: escape or exit out of the program and go to DOS, which is just a blank black screen with one of these prompts on it with a blinking cursor just waiting for your further

Proprietary Memory - Memory custom designed for a specific computer.

Protected Mode - A computer standard that guarantees particular programs receive a portion of memory for individual operation.

Protocol - A set of rules that specify how two network devices talk to each other. A protocol controls the way information is sent or received over the network.

Proxy Server - Existing between a client Web browser and a real server, a computer that caches common and often requested Web pages and holds them for easier access by users. Proxy servers allow for faster access to Web pages for groups of users in a particular area. For example, quick access to popular online services such as America Online is provided by AOL's many proxy servers, which are positioned regionally.

PS/2 port - one or two such ports are typically found on desktop and portable PCs. A keyboard and/or mouse can be connected here.

Public Domain - Software, clipart, photographs, music and other intellectual property that is available for use by the general public for free. Public domain items may be un-copyrighted or intellectual property where the copyright has run out and now available for anyone to use.

Purge - To permanently remove or delete unneeded data from a computer.