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---------------------------------------------------------------- A GLOSSARY FOR BEGINNERS ---------------------------------------------------------------- ACCESS TIME. Time required for computer to locate and read data from disk or memory. Average access time for a hard drive is determined by time required for head to locate and move to the specified track and for disk to spin around until desired data sector is beneath head. ADAPTER BOARDS or CARDS. Plug in circuit boards which can contain functions such as modems, monitor display circuits, FAX capabilities, floppy or hard disk control circuits and other functions. Adapter boards are plugged into empty slots on the main "motherboard" of the computer. ADDRESS. Location of a specific piece of computer information in computer RAM memory. Also a specific cell location in a spreadsheet (e.g., address A22 in a spreadsheet: meaning the cell at intersection of column A, row 22.) ALGORITHM. A sequence of software steps which represent a formula, method or sequence of operations to accomplish a task. ALPHANUMERIC. Containing both letters and numbers. ALT KEY. The key labeled Alt at the left of your keyboard. This key is often used by holding down Alt and hitting another key. ANSI. Acronym for American National Standards Institute which promulgates electronic and computing standards. ANSI is also used in connection with the small software program contained within DOS called ANSI.SYS which can control screen color, keyboard functions and cursor position. APPLICATION SOFTWARE. Computer programs that perform high level tasks for users. For example, spreadsheets, databases or word processing. ASCII. This acronym stands for American Standard Code for Information Interchange and represents a standard file format which uses numbers to represent keyboard characters. In the ASCII system, binary numbers from 0 to 127 represent upper and lowercase letters of the alphabet. A block of eight zeros and ones represent these characters. ASCII files, a related concept, are text files which DO NOT contain extraneous codes or control characters and are PURELY text. Word processing document files which contain exclusively text without control characters are ASCII files. ASIC. Application specific integrated circuit. ASSEMBLY LANGUAGE. Also known as machine code, the is a low level, high efficiency language which provides rapid software execution and results, but is somewhat difficult and specialized. Basic or Cobol are high level languages. Assembly is a low level language. ASYNCHRONOUS. Serial type communications between computers such that each bit at a time is individually transmitted. On an IBM compatible computer, bits are sent in blocks of eight characters made up of zeros and ones. AUTOEXEC.BAT. This batch file runs automatically when you start your computer. It is a text file containing a list of DOS commands which you can customize with your word processor or other editor to have the computer start a program, menu or other software as you wish. BAK FILES. Some software programs save older copies of data in backup or BAK files. The extension is added to the file name so that older data can be retrieved if necessary. BASIC. Beginners All-Purpose Symbolic Instruction Code. A high level programming language which usually is provided with DOS in the file QBASIC, GWBASIC, or BASICA. Provides programming capabilities which are relatively easy to learn and use. BATCH FILE (or BAT file). A text file containing a list of DOS commands to be carried out or executed. It is a small text program which can be altered or created with your word processor or text editor. Preparing and using batch files is itself a form of programming and can greatly improve the efficiency and utility of a computer. Tasks can be automated so the user does less actual keyboard work. BAUD. Bits per second. A speed measurement associated with modem communications or data transfer between the computer and printer, modem or another computer. BENCHMARK. A software program or testing method which allows similar computers or software programs to be compared. BIDIRECTIONAL. Works in both directions. Frequently associated with printers which print in both directions left to right then immediately right to left. This saves printing time. BINARY. Computer numbers represented by zeros and ones. It is based on the number two. Only two numbers are used to represent all possible values: the number 0 or 1. Binary is used by a computer since the 0 and 1 are easily represented by transistor switches which can have only two states: on or off. BIOS. Basic Input and Output System. Software related to DOS which controls input and output operations. The computer BIOS is usually stored in an integrated circuit chip which can be upgraded under certain circumstances. BIT. A single binary digit. Represented electronically as a digit one or zero inside a computer. In reality a bit is held by a transistor switch inside an integrated circuit chip. If the transistor switch is "on" the bit represented is one. If the transistor switch is "off" the bit represented is zero. Bits make up larger bytes. BOOTING or BOOTING UP or BOOTSTRAP. Refers to initial starting sequence which involves many software and hardware operations such as loading DOS, checking memory, initializing printer, etc. A reference to the computer "pulling itself up by the bootstraps." A warm boot can be done by pressing together the keys: CTRL, ALT and DEL. A cold boot is complete machine shutdown followed by turning computer on again. BUBBLE MEMORY. Specialized type of memory created by magnetizing small regions of magnetic material within an integrated circuit. This memory is nonvolatile and will not be lost when power is removed. Relatively expensive and slow in performance and thus not commonly used. BUFFER. An area of memory used to hold data temporarily. Buffers are used to hold files sent to the printer, data from the modem or hard drive or other computer inputs and outputs. The advantage of a buffer is that the computer is free to do some other work while the buffer handles the data transfer. BUG. A computer or software program error. To debug is to locate and remove an error. BULLETIN BOARD SYSTEM or BBS. A computer which can be accessed with a modem and which contains capabilities to send and receive message, send and receive software or exchange information. BUNDLED SOFTWARE. Software sold with computer hardware as part of the total purchase. BUS. Circuits which connect devices together. The main electronic path that data takes in a computer. Within the IBM PC the original 62 pins and 8 slots were connected together in a bus or interconnected arrangement which later became an industry standard. BYTE. For the IBM PC family of computers, a byte is an 8-bit unit of memory which represents one character, for example the letter E. Up to 256 different values are possible for a single byte. CACHE. A high speed area of RAM memory which holds data being read to or from a disk drive or the CPU processor itself. This saves time in that frequently used data does not have to be repeatedly found on the slower disk drive compared to the speedy CACHE in memory. CD-ROM. Compact Disk, Read Only Memory. A type of data storage on disk that uses a laser to read data. CD-ROM disks look quite similar to standard music CD's. Data can be read from a CD-ROM but not written to it, in most cases. Newer forms of CD-ROM are available which allow writing to the disk also, but are quite expensive. CELL. A single box in a spreadsheet used for data entry. CHARACTER. Letter, number or 8 bit item of computer data. CHIP. Integrated circuit consisting of silicon or other rare earth material which has thousands or millions of semiconductors etched into a tiny area. CISC. Complex Instruction Set Computer. A different method of computing compared to RISC or reduced instruction set computing. Many instructions are required to accomplish a given operation on a CISC machine compared to a RISC machine which is an newer emerging technology using inherently higher speed processor chips with fewer internal instructions. The IBM PC and clones use older CISC technology. CLOCK/CALENDAR. An computer circuit which keeps the correct time and date. Many computers contain this circuit as standard equipment. Software programs access the clock/calendar device to date and timestamp your files and provide other "date and time sensitive" operations. CLOCK SPEED. The timing frequency that a computer uses to regulate and synchronize the timing of its operations. Usually this timing speed is measured in Megahertz or millions of cycles per second. For example one might say that a computer operates at 12MHz (million cycles or operations per second). Extremely high speed desktop computers can today operate at 66MHz and 100 MHz is on the horizon. CLONE. An IBM compatible computer. CLUSTER. Two or more sectors on a circular disk track. Each track is usually divided into two clusters. COMMAND LINE. The DOS command line where you type in a DOS command to cause work to be done. Example: C>Diskcopy a: b: is a command line which will perform a computer task. COMPOSITE VIDEO. All colors of a single computer monitor are combined in a single electrical input line. An inexpensive manufacturing method which produces fair resolution at a reduced price. CONFIG.SYS. A small text file which is used by DOS when the computer first starts. This file can be edited and changed as necessary. This file informs DOS of the hardware and other capabilities within the computer. CONFIG.SYS can also be modified to control memory use within the computer. Device drivers are frequently listed in the CONFIG.SYS file. CONSOLE. A reference to a computer. Console within the DOS software CONSOLE is often referred to as CON and various commands are given such as COPY CON PRN or COPY CON FILENAME. Console in this sense means the keyboard. CONVENTIONAL MEMORY. The first 640K of RAM memory. Sometimes called DOS memory. CONTROL KEY. See CTRL key. COPROCESSOR A specialized integrated circuit which assists the main processor with math intensive operations and can speed some software packages. CPS. Cycles per second or characters per second. CPU. Central processing unit. The primary integrated circuit chip which controls computer operations. From earliest to most modern some CPU chips are: 8088, 80286, 80386, 80486, Pentium. These chips were originally designed by the Intel Corporation but have since been copied or cloned by other manufacturers. CTRL KEY. The key labeled Ctrl at the left of your keyboard. This key is often used by holding down Ctrl and hitting another key. Also called control key. CURRENT DRIVE. The disk drive the computer is using at the moment. The display prompt C> tells you that the C: hard drive is the current drive. Usually the A: and B: drives are the first two floppy drives. C: and D: are usually hard drives. CURSOR. The flashing bright square your screen which shows where information will appear when you press a key. The cursor indicates the computer is waiting for input or information. CYLINDER. A set of disk tracks at a specific location of a hard drive platter or set of platters which can be read or written simultaneously by the read/write heads. Conceptually, a cylinder looks something like an empty tin can with the top and bottom removed. DAISY WHEEL. A printer with a spinning typewriter wheel which spells out letters and characters. An early design printer. DATABASE. An organized collection of records or information which can be sorted, stored, searched, retrieved and reported upon. A database consists of records and within each record are fields containing, for example, the name, address and telephone number of a person. A record is a collection of related data items called fields. DATA BUS. An electronic pathway which carries pulses of electricity to and from the various integrated circuits and components inside a computer. Usually a data bus consists of between 8 and 32 conductive wires or lines, each capable of delivering the bits and bytes which make up computer data. Generally the more lines which make up the bus, the faster the data can travel. Older computers use 8 bit data buses. Newer PC's use 16 bit busses which can move data more rapidly. DEFAULT. A standard computer setting when nothing otherwise is specified. Can be changed in many programs temporarily or permanently. If you are not sure of a setting in a program, it may supply a default value automatically. For example a spreadsheet might "default" to blue background with white letters. This default could be changed by instructions to the software program. DESKTOP PUBLISHING. Using a desktop or portable computer to generate typeset quality text and graphics. Frequently a laser printer, special desktop publishing software and computer are combined to produce the final printed result. DEVICE DRIVER. A small software program loaded by CONFIG.SYS when the computer is first started. A mouse, for example, uses a device driver so that the computer can activate the mouse. A device driver is a type of "software link" to a piece of equipment or system within the computer. A CD-ROM also uses a device driver. DIALOG BOX. A small box on the monitor screen found in graphical user software programs that provides information or allows for selections or specific options. DIP. Dual inline pins. A type of integrated circuit chip having small pins extending in rows from either side of a plastic or ceramic chip package. DIRECTORY. An imaginary storage space on your disk which contains files. This is similar to a table of contents in a book. DIRECTORY TREE. A method for organizing data into a heirarchal structure with a main root directory at the top of the data structure and subdirectories below it. A directory tree can be diagrammed visually and is similar to a tree trunk with roots branching below it downwards and outwards. DISKETTE, DISK. A flat, usually flexible circular plastic plate covered with magnetic coatings which can be used to store information. Somewhat like tape recorder tape, but circular in shape. Diskettes come in high and low density and both 3.5 inch and 5.25 inch sizes. DISK CONTROLLER. A circuit board which provides primary control for hard or floppy disks. DMA. Direct memory access. Refers to some devices in the computer such as drives or memory which can transmit and receive data without using the CPU. This speeds software and data operations. DOCUMENTATION. Printed instructions or manuals. DOS. Disk Operating System. DOS allows you to input information from the keyboard to the computer, run programs, prepare files for disks and other necessary tasks. DOS translates users commands at a low hardware level and makes the commands available to higher level applications such as spreadsheets, games or word processors. DOS supplies a file management system for efficient storage of data on disk for processing and safe storage when the computer is off. DOS EXTENDER. A special software extension or modification to a software package which allows it to use more than the normally allowed 640K bytes of memory. Allows use of extended memory. DOS PROMPT. The small character that signals that DOS is awaiting a command. A DOS prompt usually shows the current drive. Here is an example of a DOS prompt: C> DOT MATRIX. Type of printer which uses tiny pins or wires to strike a ribbon and paper to produce images or characters. Older printers were 9 pin. Newer, high resolution printers use 24 pins. DRIVE A. The first floppy drive. DRIVE B. The second floppy drive. DRIVE C. Usually this is a hard drive. DRIVER. Software program which allows DOS to work with a specific hardware item such as a printer, mouse, trackball. DUPLEX. Communications between computers which features data transmission in both directions. Full duplex provides simultaneous transmission in both directions. Half duplex allows transmission in both directions, but never at the same time. E-MAIL. Electronic Mail. Sending and receiving messages via computers which link two or more users together. Messages are stored and retrieved as needed by individuals in the network and can be transmitting vast distances using ordinary telephone lines or other wiring. Not necessarily FAX messages, although these can be incorporated in into an E-Mail network in addition to voice, photos, illustrations and text. EEPROM. Integrated circuit memory chip. Electrically erasable read only memory. EGA. Enhanced graphics adapter. High resolution color circuit for monitor display. EISA. Extended Industry Standards Association. EMS. Expanded memory specification. Standard for using additional memory with IBM compatible computers. Memory is above the normal 640K. See also expanded memory is this glossary. EPROM. Erasable Programmable read only memory integrated circuit chip. ESDI. Enhanced small disk interface. A hard drive specification which allows high speed data transfer. Rates of up to 10 megabits per second are possible. ENTER KEY. The large key to the right of your keyboard. On many computers, this is labeled also labelled the Return key. ESC KEY. The key on your computer labeled Esc, meaning Escape. This key allows you to abort many computer entries and operations. EXPANDED MEMORY. Computer RAM memory which can be accessed only through a "window" or "page frame" set up inside the first 1 Megabyte of RAM. The usual limit of expanded memory is 32MB. Segments of this memory are quickly "paged in and out" of the memory window to create an illusion to the central processing chip of a large amount of memory. Something like flipping the pages of a cartoon book to animate a story. Many applications such as spreadsheets and databases can use this memory to handle large tasks. Expanded memory is also called EMS memory. EXPANSION CARD. Circuit card or circuit board which fits into empty slots on the main circuit board inside the computer. Adds capabilities such as video, FAX, modem, sound, parallel or serial port. EXPANSION SLOT. A socket inside the computer into which an expansion card is inserted. EXTENDED MEMORY. RAM memory which extends from the normal 1MB DOS limit to the top address limit of the CPU. Using special software it is possible to convert extended memory to expanded memory. Extended memory is useful for software tasks like RAM disks, print buffers and other applications. Many software applications such as databases and spreadsheets can use extended memory when needed for large tasks. Extended memory is also called XMS memory. EXTENSION. The last part of a filename, preceded by a dot which frequently shows the file type. In the filename MYFILE.TXT the extension is TXT. As an aside, TXT is usually a text file. A file extension ending in TMP might mean a temporary file. A file extension ending in WKS refers to a Lotus 123 spreadsheet file. EXTERNAL COMMANDS. DOS commands such as FORMAT (and others) which are retained only on disk and are temporarily loaded into ram for use then disappear from ram after a task is complete. They must be available on disk whenever used and are not normally stored in memory. FAT. File allocation table. A special area on a disk drive which keeps track of the parts of a file which may be scattered across the disk. The FAT tells the drive head where to locate the portions of data. FAX BOARD. An internal expansion board which can be plugged into the PC to allow sending and receiving of FAX documents. These documents can be stored on disk and later printed on a printer or discarded. FAX boards also allow sending and receiving of FAX documents to several clients in a row and even calling at times of reduced telephone rates such as the early morning hours - all completely unattended. FIELD. An area of the screen (frequently a database program) where data or text is entered. A field is essentially a category of information. FILE. A collection of data on a disk or in memory which has been grouped together. This can be the text of a document, numbers and formulas in a spreadsheet, or codes to run a program or application. FIXED DISK. See hard drive. FLOPPY OR FLOPPY DISK. A permanent magnetic storage medium for retaining data when the computer is off. Similar to a tape cassette. It stores data, can be erased and re-used and modified. Floppy disks are inserted into a floppy disk drive. FONT. Typefaces of a character. Size and shape of character can change. These families of typefaces or fonts have name such as Helvetica, Courier, etc FORMAT. To prepare a blank disk to receive data. Formatting involves testing the disk for possible errors and preparation of a file allocation table. FRAGMENTATION. The process which gradually allows files on disk to become widely scattered - thus slowing file retrieval. Defragmentation involves a software reconfiguration which brings file piece together in contiguous proximity for rapid access and is a routine maintenance item. FUNCTION KEYS. The keys on a keyboard labeled F1 - F10 (or F1 - F12 on some keyboards). F1 traditionally is the help key in most program and provides instructions. GAME PORT. A plug in port on the back of the computer which can accommodate joysticks or other game playing input devices. GIGABYTE. One billion bytes. GLOBAL. A software instruction or adjustment which will affect data or program parameters throughout an entire software application, document or hardware device. GUI. Graphical User Interface. Pronounced "gooey". In some respects easier to use than a DOS interface. Frequently a mouse is used to point and click through a data processing task. Point and select from a list of tasks or data rather than typing from a barren blank DOS command line. HARD DISK, HARD DRIVE, WINCHESTER DRIVE. Permanent, non- removable storage device within the computer. HARDWARE. Any part of a computer you can touch such as the keyboard, case, monitor. Software is invisible and cannot be touched although it resides within hardware. HAYES COMPATIBLE. Modems that comply with standard HAYES instruction commands which are considered an industry standard. ALso known as the AT command set which stands for "attention" in a HAYES modem. HEADS. A reference to the read/write heads of a floppy or hard drive. They are small electromagnetic coils attached to an arm which moves freely over the surface of the spinning platter or disk. Electric pulses to these coils creative small fields of magnetism on the spinning surface below the heads. HEXADECIMAL. Numeric system using base 16. Most memory locations in a computer are calculated and displayed in hexadecimal notation due to memory design considerations. HIDDEN FILES. Files which are present but have been temporarily hidden using DOS commands. Cannot be seen on an ordinary director listing or search. HIGH LEVEL FORMATTING. Is a process performed to a hard disk after low level formatting (see below). This high level format creates the directory structure of the disk (or file allocation table area) which DOS will later use. HIGH LEVEL LANGUAGE. Computer programming language which is relatively easy to learn and use. Examples: BASIC, COBOL, PASCAL. IC. Integrated circuit. Also known as chips. ICON. A small visual or pictorial symbol used to represent a software program, task or item of data. Used especially with GUI or visual interfaces. A mouse frequently maneuvers a pointer to an ICON which is then selected by clicking (depressing a button on the mouse) when the mouse pointer is on the ICON. IDE. Integrated drive electronics. The term is associated with high performance hard disk drives which contain the central drive controller built into the hard drive instead as a separate controller card which was used by earlier hard drives. An IDE hard drive is optimized for AT class computers using 286, 386 or 486 CPU (central processing unit). IDE drives are, in general, fast and reliable. INK JET. This is a reference to a type of printer which forms characters and images by spraying tiny jets of ink on either plain paper or specially coated paper stock. INPUT DEVICE. Hardware used to enter or send information on a computer. A mouse, keyboard, game joystick, or trackball are input devices. INTEGRATED SOFTWARE. A type of software package which frequently combines several standard software applications into one entity. Frequently an integrated package will contain a spreadsheet, database, word processor and perhaps and modem or telephone dialing program. INTEGRATED CIRCUIT. See CHIP or IC. INTERLEAVE FACTOR. The spacing of non-consecutive sectors around the track of a hard disk. Usually this is given as a ratio. Optimal interleave configures these non-consecutive sectors for speedy data retrieval from the hard disk. Example: an interleave of 1:1 is considered very fast in hard drive performance characteristics. INTERNAL COMMANDS. Commands of DOS which are loaded into RAM memory and do not require the DOS disk to be present to function. Examples: DIR, COPY, RD INTERPRETER. Software program which translates high level programming instructions into low level machine or assembly code which the CPU can process. Example: DOS contains a Basic interpreter which you can use to write your own programs. It is a form of Microsoft QuickBasic. Interpreted programs usually require that the interpreter (example, QBASIC.EXE) be present to run the program compared to more advanced compiled programs which DO NOT require that an interpreter be available for the program to run. KB, KILOBYTE or K. Refers to one thousand bytes. More precisely this is 1024 bytes. LAN. Local area network. Circuits to allow several or many computers to talk to each other and share data. Of interest to business and office computer users, but of only passing interest to home and home/office users having only one machine. LASER PRINTER. Type of printer that uses a rapidly scanning laser beam to build characters on a rotating drum which in turns transfers images to toner ink and paper. LOW LEVEL FORMAT. A preliminary process which is usually given to a hard drive to prepare it for accepting data. Low level formatting establishes tracks and sectors on the disk so the drive can accept data and locate it for later retrieval. Normally this will destroy all previous data! Low level formatting is usually given to a hard drive at the factory, although end users may also wish to low level format a drive for various performance reasons. LQ. Letter quality printer. MACRO. A sequence of keystrokes or commands that can be recorded and played back to execute a program or task of data entry thus saving you keystrokes. In telecommunications (modem) software, macros are also referred to as scripts. Many programs such as spreadsheets, databases and word processors have a macro "language" which allows you to adapt the program to automatically perform a sequence of tasks rapidly instead of using tedious repetitive keystrokes. Using and preparing macros is itself a form a programming. MAINFRAME. Large or corporate computer as compared to a smaller desktop computer. MASS STORAGE. All disk-oriented forms of data storage such as hard and floppy disks, optical disks and backup tape drives. MEGABYTE, MB or MEG. One million characters or memory areas. MEMORY. A storage area inside your computer. Usually within individual integrated circuit chips. Data stored in memory disappears when the power is turned off and must be stored on a diskette or other non-volatile memory device. Also called RAM (random access memory) or simply RAM. ROM (read only memory) is another type of memory which is used when the computer starts and is cannot be changed or rewritten. ROM is also stored in a different type of integrated circuit than RAM memory. MEMORY ADDRESSABILITY. The number of separate individual memory locations in RAM with which the CPU is capable of communicating. MEMORY MANAGEMENT. The process of selecting and controlling the assignment, use and location of software within RAM memory. Careful memory management can speed software and allow for larger data processing tasks or the operation of several software programs at the same time or via rapid switching. MEMORY MANAGER. A type of software program that can increase the amount of available useful RAM memory by making extended or expanded memory available to primary software applications such as your spreadsheet or word processor. Later versions of DOS contain small memory management programs which can be installed via adjustment of the CONFIG.SYS and AUTOEXEC.BAT files. MEMORY CACHE. An area in RAM memory, usually about 8K to 128K in size, which the CPU can use to store frequently accessed data rather than going to a hard drive or floppy disk. This speeds up operations. MENU. Display of choices or options on a list. You can select one of the menu options with a mouse or by typing a letter. Then the menu will run the software program you have selected. MFM. Modified frequency modulation. An early standard for hard disk data storage and transfer. MHZ. Megahertz or one million cycles per second. Derived from the name of Rudolf Hertz, an early electrical researcher. MICROPROCESSOR. See CPU. MILITARY TIME. A numerical time designation featuring 24 hours in a day. For example, 1300 hours means 1PM. 2400 hours is midnight. Basically, add 12 to the number of hours if a PM time is shown. Military time is the standard used by most computers for clarity. MODEM. Derived from MODulator DEModulator which allows computers to transfer information over phone lines. MODES. When referring to CPU chips there are three modes: real, protected and virtual which address memory in various ways. Early 8088 processors have only REAL mode. More sophisticated 80386 processors have all three modes which allows for greater RAM memory access and more sophisticated software applications. MOTHERBOARD. Usually this is the largest circuit board within the computer case and it contains the RAM memory, central processing unit and expansion slots into which other boards are plugged. MOUSE. Hand operated pointing and selection device which serves as alternate input to the keyboard. MPC. Multimedia PC. A special type of computer designation developed by Tandy Corporation and Microsoft which describes minimum standards for computers which can run multimedia software which makes use of sound, animation and frequently also CD-ROM disks. The MPC rainbow logo appears on computers configured for this type of use, although other types of computers can be made MPC-capable by adding the requisite hardware. MULTIMEDIA. Computer presentations or software which make use of sound, extensive graphics, animation and video in a colorful highly detailed manner. MTBF. Mean time between failures. A measurement of relative reliability related to components such as hard drives or other devices. MULTITASKING. A computer which can perform several operations at the same time. NLQ. Near letter quality printer. NULL MODEM CABLE. Special electrical cable used to transfer data between two computers. ONLINE SERVICE/BBS/BULLETIN BOARD. Computers connected to telephone lines which users can access by modem. Messages to other users can be left and retrieved. Software can be sent (uploaded) or retrieved (downloaded), databases can be searched for information. OPERATING SYSTEM. Another name for DOS. The essential "core" software which itself runs other programs and talks to the keyboard and printer. There are other operating systems besides DOS. For example UNIX, OS/2, Windows, CPM. OS/2. Operating system 2. A proposed update to the DOS operating system. PAGING. The ability of software and hardware to store a portion or segment of software instructions on the hard disk and then retrieve it a later time. This allows conservation of limited RAM memory. PARAMETER. Information sent to a program. Example: /p is the parameter of the DOS command DIR/p. Parameters modify a software command. PARITY CHECK. An error detection method used to test RAM memory chips and assure reliable data transfer. PARKING THE HEADS. Refers to the process of running a software program to cause the read/write heads of a hard disk mechanism to move to a track area of the disk which is of low use or is a designated safe zone. Somewhat like lifting the needle from a phonograph record and placing it on the "needle rest." This prevents the possibility that the heads will drop or otherwise gouge into the soft magnetic surface of the platters below. The heads are usually parked while the disk is spinning and once parked the machine is turned off. Early MFM and RLL hard drives are usually parked by issuing a software command prior to shutdown. Modern IDE drives park themselves automatically when turned off. PARTITION. A subdivision which is created by the FDISK utility of DOS. A partition can be used to subdivide a hard disk into more than one logical drive (e.g., C: and D:) or run various operating systems from the same disk such as DOS and Unix. It is usually established after a preliminary high-level format process. PATH. A list of subdirectories where DOS searches for information. In a way it is a map or "route" which DOS searches for information. You can set this with the DOS PATH command. The path command is usually set within the AUTOEXEC.BAT file mentioned above. See the DOS path command for syntax. PASSWORD. A word or phrase which must input at the keyboard before a program or operation can begin. PLATTER. The physical disk medium of a hard drive or floppy system onto which data is recorded and read back. Usually a platter refers to a hard drive disk which is aluminum and coated with a metallic iron oxide. POINTING DEVICE. Mice, trackballs, light pens and so on allow input to the computer in addition to the more conventional keyboard. PRESENTATION GRAPHICS SOFTWARE. Programs which produce charts, text or images for businesses presentations. The illustration or chart is designed on the computer screen and then finally output to a lecture slide, overhead transparency, printed sheet or even computer screen image which will later be viewed. PROMPT. See system prompt. PROTECTED MODE. A unique feature of the 80286 (and later) Intel CPU chip to access RAM memory beyond the 1MB limit as well as manage and protect multiple software programs in memory. PROTOCOL. Software standards and software programs which ensure reliable data transfer without error loss. RAM, RANDOM ACCESS MEMORY. Temporary memory in your computer (random access memory). When you turn the computer off, all RAM contents are lost until replaced from data stored on a disk. RAM resides inside small integrated circuit chips. REAL MODE. A unique feature of the 80286 (and later) Intel CPU chip which allows simulation of the 1MB memory limit and instructions of the older 8086 CPU which allows operation of older software programs. This is an example of "downward" or "backwards" compatibility. REBOOT. Touch the Control (Ctrl), Alt (Alt) and Delete (Del) keys all at the same time. This restarts your computer without turning it off. This is also know as a "warm reboot" as compared with a "cold reboot" which means complete shutdown with via the on/off switch. RECORD. A set of information elements in a database. For example the data Mr. Smith including his address, income, telephone number and occupation would together constitute a single record. RELATIONAL DATABASE. A database software package which can interrelate multiple databases (e.g., parking ticket database AND policemen on the force AND parking meters which are out of order - each of these databases is a separate file, but a relational database can interrelate them and produce very complex reports and find unique relationships.) Relational databases often contain complex command languages, application generators, query systems, specialized report writers, SQL support and more. RESIDENT COMMANDS. DOS commands such as COPY, TYPE, DIR, DEL which are retained in RAM instead of disk. Also called internal commands. They are available at all times when DOS is in operation. RESIDENT PROGRAM. Program(s) which are loaded into your computer temporarily and remain available until the computer is turned off. Resident programs are also known as TSR programs (terminate and stay resident.) Resident programs are "popups" such as calendars, calculators and other devices. RGB. Red, green blue. Reference to type of monitor or display system. RGB monitors on early computers were frequently associated with the CGA or low resolution color display standard. RLL. Run length limited. Hard disk data storage and transfer scheme. Provides fifty percent high data density storage than older MFM system. RLL is itself a somewhat antiquated type of hard drive, but still in use in many machines. IDE hard drives are a more popular option today. ROM. Read only memory chip. Memory is not lost when computer turned off. ROOT DIRECTORY OR ROOT. The main directory on a disk. You are not in a lower subdirectory area (e.g., C:\doc\wp\files) but in the main directory (e.g., C:\) SCSI. Small computer systems interface. Frequently pronounced "scuzzy." A hard drive scheme which allows multiple hard drives to be attached and high data transfer rates. SCANNER. A device which can convert a printed image such as a photo or illustration to a digital image within the computer memory. Some scanners use OCR (optical character recognition) to scan text documents containing printed words and convert them to text characters in the computer as if a person had typed the document. These scanned documents or illustrations can then be edited, transmitted or stored as desired. SECTOR. The smallest unit of storage on a hard or floppy disk consisting of 512 bytes - typically there are either 17 or 26 sectors per track on a hard drive. SERIAL. Data is transmitted one bit at a time. In comparison, parallel data transfer sends eight bits at a time. SIG. A special interest group of a computer club. Perhaps a general purpose computer club might contain a SIG for word processing users. And perhaps another SIG for those interested in databases. SIMM. Single inline memory module. Type of integrated circuit. Usually a type of plug in memory module which adds more RAM type memory to a computer. Currently this is the most common configuration for RAM memory on modern computers of the IBM clone type. SIP. Single inline pins. Usually a type of plug in memory module which adds more RAM type memory to a computer. SOFTWARE. Programs used to manage the operations and data contained within a computer. A set or list of instructions a computer uses to accomplish a data processing task. SOURCE. When doing file or disk copies, refers to the originating disk or file. SPOOL or SPOOLER. Simultaneous peripheral operations on line. A memory storage buffer which holds data which can be fed to printer, modem or other device while main processor is used for other applications. SPREADSHEET. A software program which simulates an "electronic grid" or sheet of accounting ledger paper and divides the monitor screen into rows and columns into which data and formulas can be input. Spreadsheets in some cases also contain database and word processing functions and are quite flexible. SUBDIRECTORY. A directory of files on a diskette or hard drive which is located within or below a "parent directory". The root directory, the highest directory, is never a subdirectory. SYSTEM PROMPT. When you look at your monitor screen and see the DOS display such as: A> or C> you are looking at a system prompt. You must next give DOS a command to run a program or perform a DOS operation. TARGET. The file or disk to which data is sent. If you are copying a file from a disk in the A: drive to the B: drive, then the B: drive is the target drive and contains the target disk. TELECOMMUNICATIONS. Transmitting via electronic means data or information, usually over telephone lines. A modem is used for this task. Data, sound, pictures, video and FAX are all transmitted via telecommunications methods. TRACTOR. Printer with sprocket feed which handles paper perforated along the edges. TRACK. Concentric rings or circles of data sectors on a disk platter which contain data and mark position points for the read/write heads. TRACKBALL. Somewhat like an upside down mouse. A large ball is cradled in a plastic holder. As the ball is turned or rotated a pointer on the computer monitor moves. Switches next to the ball allow items on screen to be selected. TROJAN HORSE. Type of software which may contains hidden code which will damage data. TSR. See resident programs. TSR is an acronym for "terminate and stay resident" and is a type of software program that can remain in background and then "pop up" over a software package for brief use. For example, a pop up TSR calculator. TURBO. High speed computer setting which operates the CPU at high clock speeds. USER GROUP. Computer club. VAPORWARE. Announced software product which has not yet shipped. VGA. Video graphics array. A circuit, usually on a plug in card, which provides high resolution video output to the monitor. VIRUS. Software program which is self-replicating and can cause loss or damage to data or other software programs. VOLATILE. Memory which can be lost if power is turned off. VIRTUAL 8086 MODE. A unique operating feature of the Intel 80386 CPU chip that can provide several DOS software programs with a 1MB section of RAM memory which each act like a "separate small 8086 computer" which is running in real mode. WINDOWS. Software package from Microsoft Corporation which provides ease of use featuring point and click menus and screens. Also refers to capability of any software package to open a small window on the screen over an existing software package or to split the screen into subdivisions so that several documents or data sets can be examined simultaneously. XMS. Extended memory. See extended memory elsewhere in this glossary. Tutorial finished. Have you registered PC-Learn to receive your bonus disks? Registration is encouraged. Shareware works on the honor system! Send $25 to Seattle Scientific Photography, Department PCL6, PO Box 1506, Mercer Island, WA 98040. Latest version of PC-Learn and two bonus disks shipped promptly!