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# or symbol


# or Symbol

4th generation languages (4GL)
Very high-level languages. These are results oriented and include database query languages

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access slot
Opening in the back of the computer to allow devices to connect to peripheral cards
acoustical modem
A modem in which the telephone handset is placed into the device, which is connected to the computer.
activation code
A code needed to 'activate' a newly installed program or service. This is different from a registration code, which shows that you bought the product. Activation codes are usually good for only one use.
adapter card
See expansion card
A very fast data transfer method that uses normal phone lines to handle phone calls and data transfer at the same time. Download rates of 512 KBps up to 8MBps.
add-on program
Requires another program to be of any use
analog signal
Variations (modulations) in a signal used to convey information
animation  animation: eyes
A sequence of images that are shown one after the other very quickly. The human eye and brain blend the images to produce the effect of motion.
animation effect
A motion applied to a slide or part of a slide in a presentation.
antivirus program
A program which finds and eliminates computer viruses
application or app
A computer program
Arithmetic/Logic Unit (ALU)
The part of the CPU that executes the computer's commands by doing arithmetic or the logical comparisons <(less than),> (greater than), and = (equal to).
A code system for turning letters, numbers and symbols into digital data. Used for PCs.
assembly language
Abbreviations for machine language

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background task
A task of low priority. Will be given fewer time slices.
A copy of a file or set of files
band printer
Uses characters on a chain that is moved into place before striking the characters onto the paper.
Beginner's All Symbolic Instruction Code Written in 1964 for college students to use to learn programming concepts.
Place in a computer case to put drives and other devices
bi-directional cable
Allows the printer to send messages to the computer as well as receive data for printing.
Having two values only, like 0 or 1.
Basic Input/Output System. A limited set of instructions to the computer which gets it started.
Short for "binary digit". One on/off position in a digital number
An image whose format describes each dot in the digital image
A logical division of data on magnetic tape.
Starting the computer
Line around a page, table, or image
Bits per inch. A measure of recording density for magnetic tape.
Connects networks of the same type
Period of lower voltage
browser hijacking
Taking over of your browser without permission by malware, changing the home page or Favorites, sending you to sites that you did not want to see.
A tool for drawing in a graphics program.
Location for temporary data storage while processing is going on
Any path that data travels inside the computer
bus width
Amount of data that the bus can carry at one time. Measured in bits.
bus configuration
Network configuration where all devices are connected to the same communications line
A graphic which looks like you could press it. Clicking on a button executes a command.
8 bits

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C, C++
Programming language originally created for writing system software. C has evolved into C++. Both are widely used by programming professionals for all sorts of programs
Digital device that records moving pictures.
Digital device that takes single pictures.
capacity (disk)
Amount of data that can be stored
Menu: Additional menu(s) appears below or to the right of item in a mene
cathode ray tube (CRT)
Device which displays computer output. From the physical mechanism used for the screen. New computer systems use LCD monitors instead.
Recordable compact disk. Disk can be written to by a user with the proper kind of CD drive. Cannot be erased to be written on again. Once time write only!
Compact Disk-Read Only Memory. The most common size of optical disk. Laser used to read bumps on disk as 0 or 1 for digital data. Made from mold of original disk in a factory. Data can only be read, not written.
Rewritable CD disk. User can save data to the disk, erase data, write new data to the same disk. Made of different materials than CD-ROM or CD-R disks.
A single image in an animation sequence
Intersection of row and column in a table or on a spreadsheet.
Color Graphics Adapter, an old video type with maximum 320 x 200 resolution
chain printer
Uses characters on a chain that is moved into place before striking the characters onto the paper.
A graphical representation of data
A program that lets you exchange messages with other people who are online. Everyone in a particular conversation can read all the messages.
client server
A server which processes a request and returns the results to the requesting computer, the client
clip art
Pre-drawn pictures to add to documents
A section of computer memory used to temporarily hold data that has been cut or copied for transfer to another document or location within a document. The Windows clipboard can only hold one thing at a time. The Office clipboard can hold around 23 different copies.
A program or file is "in the cloud" when it is stored on a server that can be accessed over the Internet.
A set of track sectors which is the minimum space used by a read or write.
CMYK color system
Cyan, Magenta, Yellow, and Black. These ink colors are all that are needed to create all the printed colors.
coaxial cable
Round insulated wire with single wire in center. Tightens down with collar.
Common Business Oriented Language Written about 1960 with business applications in mind. It has a very English-like structure, using sentences and paragraphs.
cold boot
Computer is shut down completely, hard disk stops spinning, several seconds elapse at least before a restart is attempted.
Folder Tree: Clicking an arrow or similar symbol closes up an expanded list of the contents of a folder.
Layout: columns of text side by side, as in a newspaper
Spreadsheet or table: vertical section of cells
command language interpreter
Program that translates your keystrokes into the 0's and 1's that the processor understands.
Special codes or keywords that tell the computer to perform a task, like RUN "SALES"
Programs that temporarily connect computers to each other to exchange information.
communications channel
Is the path that the data follows as it is transmitted from one computer to another. Also called a communications line or link,
communications link
See communications channel
communications line
See communications channel
Rewrites the program into machine language that the CPU can understand. The program is then saved.
An electronic device that executes the instructions in a program. A computer has four functions: inputs data, processes data, produces output, and stores results
computer output microfilm (COM)
Device that generates microfilm direct from the computer
computer language
Language with which we can communicate with the computer
Smoothes out variations in power by pumping up the voltage when it drops and stepping it down when it's too high
contact manager
An advanced kind of Personal Information Manager which allows you to keep track of when you had a conversation or a meeting with someone and what was done or said.
The metal strips that meet matching metal to create a connection. In a removable solid state device, these are usually inside a rectangular connector.
What happens depends on exactly what is going on at the moment, or exactly where the cursor is. A right click in Windows since Win95 will open up a context-sensitive menu, which has different options depending on where the mouse is.
continuous speech recognition
A voice input system in which the speaker may use normal conversational flow.
continuous-form paper
Paper for track-feed printers. Must be separated at perforations.
control unit
Part of the CPU that controls the Machine Cycle
Duplicate selection onto Clipboard
Memory device consisting of small metal rings. Magnets tip a ring to left or right, which represents on and off. Relatively slow
Characters per second. Measures printer speed.
Central Processing Unit. Composed of Control Unit and Arithmetic/Logic Unit.
CPU utilization
Measures the time the CPU is working and when it is idle.
Computer:A sudden shutdown or failure to respond by a program or the whole computer. Can be caused by a hardware failure or by a programming error but also by power surges and brownouts. Sometimes the issue is not having enough RAM or free hard disk space.
Hard drive: Head crash- occurs when the read/write head makes physical contact with the disk. This causes damage and may stop the drive completely.
create (document)
Start a new document
Shareware which has important function disabled
Symbol marking where text will appear when you type
custom install
A choice offered when installing new software. You will see one or more choices such as what folder to put the program in, whether to create a shortcut on the Desktop, what parts of the program to install.
Remove selection from document and store temporarily on the Clipboard, which is a section of computer memory.
A set of matched tracks from storage disk surfaces.

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The raw facts given to the computer, like first name, price, quantity ordered
data automation
Making data entry and validation as automatic as possible
A program to manage lists that are not entirely numbers, such as addresses, phone lists, inventories... A database is made up of files which contain records which are make up of fields.
data communications
Transmission of data and information over a communications channel,
data compression
Program which force data into less space on the storage medium
data entry
Process of putting data into computer-readable form, especially typing in data but also scanning and other methods of getting data into the computer.
data recovery
Program which attempts to recover deleted or damaged data
data transfer
Moving data from storage disk to comoputer. Measured in kilobytes per second (KBs).
Look for and remove errors in a program
A step in the Machine Cycle. The processor must turn an instruction into machine language.
The original settings; what will happen if you don't change anything
Puts files on storage disk so that the whole file is in sequence rather than stored with parts in various locations on the disk
Remove selected object (not saved anywhere)
density (tape)
How close bits may be placed on magnetic tape. Measure in bits per inch (bpi)
Computer: personal computer that will fit nicely on a desk
Interface: What shows on the monitor when no programs have been opened. In Windows the desktop normally has shortcut icons to programs and documents that you use often.
desktop publishing (DTP)
Program which give precise control of where text and graphics appear on the page
dialing software
Tells the computer how to place a call on the phone line connected to it. Display messages about call progress
Having specific values, not continuous values. In particular related to binary digital data for modern computing.
digital camera
Device which takes still photos but records the pictures on computer disks or memory chips
digital info
Information stored as a string of zeros or ones
digital ink
A way for a computer or tablet to record your actual handwriting
digital signal
A stream of 0's and 1's.
A grouping of files. More currently called a folder.
directory tree
Hierarchy of directories
discrete speech recognition
A voice input system in which the speaker must pause between words for the computer to tell when a word stops.
disk management
Program involving formatting, partitioning, and defragmenting your disk
Used for storing data. Made of Mylar with an oxide coating. 5¼"and 3½" sizes exist with the smaller size dominating now. Also called a floppy or floppy disk.
display terminal
A device that is primarily a screen and a keyboard. If it does no processing itself, it is a dumb terminal. If it can do some processing, it is a smart, intelligent, or programmable terminal.
distributed computing
Using computers over the Internet or another network to perform part of a complex task
The printed or online documents that explain things: identify the parts of your hardware or software, give installation instructions, give directions for use. In programming this includes explanations of the code - why it is written that way, what the code is doing.
Disk Operating System. MS-DOS was from Microsoft. PC-DOS was from IBM.
dot matrix printer
Forms characters using row(s) of pins, 9, 18, or 24 which impact the ribbon on top of the paper
dot pitch
Distance between dots on a monitor screen. Several ways to measure. May be measured from center to center between nearest dots or between dots of the same color (for color monitors). May be measured from center to vertical line through nearest dot of same color - a shorter distance than center to center.
double-sided disk
Top and bottom surfaces of a storage disk are used.
Transfer a file to your computer from elsewhere
Dots per inch. Used to measure printer resolution.
draft quality
Quality good enough for a test print or for internal use
drawing program
A graphics program that deals with images as a set of geometric shapes. Each shape is defined by a vector, an equation. Has smaller file sizes and resizes with little loss of picture quality. File formats include cdr, cgm, cdx, drw, wmf, wpg and many more.
The software needed for hardware to communicate with the computer's operating system.
dual boot
Being able to choose between two or more operating systems when turning on your computer.
dumb terminal
A terminal which cannot store or process data
Types of DVD discs. DVD discs commonly contain movies or programs or back-up copies of data. DVD-R and DVD+R are recordable discs - one time only. DVD-RW disc can be recorded, erased, and recorded again.

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A code system for turning letters, numbers and symbols into digital data. Used on main frames.
Make changes in a document
Extended Graphics Adapter, an old video type with maximum 640 x 350 resolution
Electronic mail - sending messages over a network or Internet connection
Changing data with a coding scheme to keep others from reading the data.
end user
Person who actually uses hardware or software
enter (text)
Pressing the ENTER key to accept what you typed as part of the document.
A file which runs a program
A step in the Machine Cycle where the processor performs the action that the current instruction ordered.
Command to close a program.
Folder tree: Click an arrow or similar symbol to show the contents of the folder in the folder tree.
expansion board
See expansion card
expansion card
Card which plugs into a slot on the motherboard. Also called controller card, adapter card, interface card, expansion board.
expansion pack
A program that expands the features of a program you already have, such as adding new game levels, new characters, new weapons, new skills.
The part of a file name after the dot character. The extension tells what the file's type is - Word document (.doc or .docx), text file (.txt).
external device
Plugs into the computer instead of being inside the case.

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female connector
Cable connection with holes to match pins on the matching connector
A step in the Machine Cycle where the processor gets the next instruction.
fiber optic line
Made of glass fiber for transmitting data
field (database)
A single item that is part of a record in a database
Something saved on the computer - a document or program
file (database)
A collection of related records
file attributes
Properties of files, including Read-Only and Hidden.
file transfer
Moving a file from one computer to another
file server
A server which returns a file to the requesting computer for processing there
file management
Program to help you create, move, rename, delete etc. files
file name
Has two parts: FILENAME and EXTENSION in the form filename.ext
file type
File name's extension identifies the type of file - doc, txt, htm, exe, and so forth. Each type uses a different way to encode the document.
A tool which changes the color of a section of an image.
A program or hardware configuration intended to keep outsiders from accessing your computer without permission.
flash memory
Type of memory card for storing files. As an external device, used in USB flash drives. Also used in solid state drives.
flat database
A database composed of records which have fields. Each record must contain all the information you want about that record. A spreadsheet can be used as a flat database, if each row is a single record.
floppy disk
See diskette
flow chart
A visual representation of the flow of logic in a computer program
A grouping of files
folder tree
Hierarchy of folders
Combo of typeface & point size, includes styles such as BOLD, italics, underline
The bottom part of a page that is repeated on every page of the document
Amount of physical space something uses
foreground task
A task of high priority. Will be given more time slices.
Disk: sets up a method of assigning addresses to the different areas of a storage medium. It also sets up an area for keeping the list of addresses.
Document:arranging the look of the document by selecting the typeface, font size, text color, spacing of lines and words, etc.
File: See file type.
An equation used to calculate values such as interest or mortgage payments
From Formula Translation. Created around 1957 to help scientists, engineers, and mathematicians write software for mathematical models of complex events, like nuclear blasts and space flight.
free space
The part of a storage area that is not being used.
Program which is given away for free
friction feed
Uses pressure to pull single sheets through a printer
File Transfer Protocol. A protocol for moving files between computers. Also a program that uses this program is an FTP program.
full path name
Lists the route to a file starting with the drive name and naming all the folders/directories, like c:\documents\memos\123197.doc

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gap, interblock
Gap which separates logical blocks on magnetic tape
gap, interrecord
Gap which separates records on magnetic tape
Connects networks of different kinds
GHz = GigaHertz
A measure of cycles of electricty or a process. 1 Hertz = 1 cycle.
grammar checker
Looks for grammar/style errors. Cannot always tell if there is an error or not. You must know what you meant to say.
graphical user interface (GUI)
Uses images like icons and buttons in the user interface to make it easier for the user. Sometimes pronounced GOO-ee.
Pictures and charts
Computing: The set of separate computers uses in distributed computing.
Spreadsheet: The lines separating cells.

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A small square or circle or other symbol which you can drag to change the size or shape of a drawing object or a window.
hand scanner
Device that is moved by hand over the document or picture to convert it to a digital image
hard copy
Printed on paper or other permanent media
hard disk
Magnetic storage device consisting of 1 to 4 metal platters which are sealed inside a case. Usually installed inside the computer's case, though there are removable and cartridge types.
hard drive
Device that controls the reading from and writing to a hard disk.
The physical parts of the computer
The part of the disk drive that does the reading and writing of data
Area at the top of a page that is repeated on every page of the document
Base 16 numbers.
high-level language
Use program statements - words and algebra-type expressions. Developed in the 50's and 60's
Showing what is selected by changing the background color around the selection.
host computer
Computer which handles the network tasks and holds the data
HyperText Markup Language = the coding used to create web pages.

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A small graphic which when clicked runs a program, executes a command or opens a document.
impact printer
Printer in which something strikes paper and ribbon together to form a character, like in a typewriter.
Data that has been processed into useful form
ink jet printer
Printer that sprays ink onto paper to form characters
Everything you tell the computer
input device
Device used to give the computer data or commands. Includes keyboard, mouse, scanner, etc.
input/output storage
Where keystrokes and data are stored as they are input before being processed or as the results are ready for output.
Add text at location without overwriting existing text
Integrated Software
A program combining the basic features of several other programs.
internal device
Plugs into a slot inside a computer
Program which translates the program statements into machine language one line at a time as the program is running
See "chat"
ISA slot
Older type of slot on motherboard for peripheral device boards
ISDN terminal adapter
Integrated Services Digital Network. A digital device which connects a computer to a digital communications line
instant messaging
A program which notifies you when your "friends" (people on your list) are online. You can write them messages which they receive right away (instantly). Usually only the person you send a message to can read it.

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A popular language which is used to write both full computer applications and small applets for web pages. Its goal is to create applications that will run on any computer, unlike other languages which are not cross-platform
A scripting language used mostly on web pages. Not related to Java.
A device which controls cursor motion with a vertical stick. Usually has more buttons than a mouse. Used in flying games especially.
A small piece that slides over two pins at the same time. Jumpers are used on the motherboard, hard drives, and some peripheral cards.
Alignment of text: left, center, right, justify (or full) = both left and right edges are straight.

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Part of the operating system needed to start the system
Input device with keys for letters of the alphabet, numbers, and various symbols.
kilobyte (K or KB)
1024 bytes historically and in some current uses. New standards will use kilobyte for 1000 bytes and kibibyte for the binary 1024 bytes.

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Local Area Network. Computers are relatively close together.
Orientation for a document where the width is wider than the height.
Portable personal computer with a screen in the cover.
Arrangement of text and graphics
letter quality (LQ)
Quality of best typewriter output
Liquid Crystal Display (LCD)
Screen type used previously in laptops and other small screens but also now in large desktop monitors. Flat surface with thin body. Uses 3 subcells per pixel to create color with RGB color (Red, Green, Blue).
An open source operating system.
A free version of a program which is missing some high-end or desirable features
login, logon
Procedure where user must identify himself to the computer to continue
long file name
Has more characters than 8 for filename and/or more than 3 for extension
Lines per minute. Measures printer speed

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machine cycle
One round of steps from getting an instruction back to getting the next instruction. The four steps are fetch, decode, execute, store.
machine language
The language of the CPU. The lowest level language. Composed of 0's and 1's
Small program to automate actions within a major application
magnetic ink character recognition
Machine reads characters printed with a special ink with magnetic properties. Used on bank documents
magnetic disk
Storage device which uses magnetism of the surface to store data
magnetic tape
A storage medium using a long tape with magnetic properties.
main circuit board
The largest circuit board in the computer, to which all peripherals and the CPU attach. Also called motherboard.
main frame
Computer that is the heart of a network of computers or terminals which allows hundreds of people to work at the same time on the same data. It requires a special environment - cold and dry.
main memory
Where the computer stores the data and commands that are currently being used.
male connector
Cable connection with pins to match a connector with holes
Any of several types of programs that do undesirable things to your computer. Includes viruses, trojans, worms.
Space at the borders of the page or other document object
mass storage
Sets of cartridges containing data. Accessed using robot arms.
megabyte (MB)
1024 kilobytes historically. Different scientific and technical areas are using the words for quantity differently. For data storage devices and telecommunications a megabyte is 1 000 000 bytes.  For data transmission in LANs a megabyte is 1 048 576 bytes as described above.  But for data storage on a floppy disk a megabyte is 1 024 000 bytes!

A new set of words has been created to make it clear what size is really being used. See  http://physics.nist.gov/cuu/Units/binary.html for a further explanation.

megahertz (MHz)
1 million cycles per second.
The part of the computer used for current data and results. RAM chips store this data until it is stored or output. Sometimes 'memory' is used for storage devices like flash drives but those are not part of the computer's memory at all.
memory address
The unique numerical name for a location in memory
memory management
Program to handle where in RAM programs put their data
memory speed
How fast data can be moved into and out of RAM chips.
Part of a user interface which lists the available commands. A menu item might contain other commands as a submenu
Also known as Personal Computer (PC)
Silicon chip containing the CPU, ALU, and some memory
One thousandth of a second. 1000 ms = 1 second.
Size of computer between the PC and a main frame. Originally developed to do tasks requiring intensive calculations to relieve the load on the main frame.
minimum install
A choice offered when installing a new program. Will install only the basic features and will leave out features that the authors don't expect many people to use.
Millions of instructions per second. A measure of computer speed.
Device which translates between the analog phone line and the digital computer. From Modulate/Demodulate
Device which displays computer output. From its use to "monitor" progress of a program.
One color text on one color background, like white letters on blue or green characters on black
Main circuit board of the computer. Has on it the CPU, memory boards, device boards, power plugs, etc.
An input device consisting of 2 or more buttons with a rolling ball underneath or a laser to detect motion. The pointer on the screen follows the motion of the mouse ball.
Using more than one CPU at the same time
Combination of sound and images with text and graphics. This would include movies, animations, music, people talking, sound effects like the roar of a crowd and smashing glass.
Programs take turns using the processor.

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nag screen
Screen that reminds you to pay up each time you run a shareware program
nanosecond (ns)
1 billionth of a second. Used to measure memory speed
natural language (input)
A voice input system which recognizes normal human speech
natural language (programming)
5th Generation Languages. We don't really have any programming languages yet that use natural language. In such a language you would write statements that look like normal sentences.
near letter quality (NLQ)
Print quality nearly as good as best typewriter output
Putting directories or folders inside other directories or folders
A small computer which smaller than a laptop or tablet computer. Expected to be used primarily for browsing on the Web.
A set of computers which are linked together on a permanent basis
network cable
A cable that connects a computer or other device to a network. This may be an round patch cable with a connector that looks much like a telephone connector or a coaxial cable with a screw-down collar.
network hub
A device that handles traffic across the network but does not do any processing.
network switch
A more sophisticated device that handles traffic across a network.
A discussion group on the Internet where messages and responses are posted for all to read
Each device connected to a network
noise filter
Removes from a signal the interference caused by the magnetic fields of nearby devices
non-impact printer
Type of printer does not involve actually striking the paper. Instead, it uses ink spray or toner powder.
Describes memory which retains data even when the power goes off.
no-print area
The part of a page that the printer cannot print on for physical reasons. The print heads cannot move to that area.

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OCR software
Software which changes a scanned document from an image to editable text
open source
Programs who make the underlying source code public and allow anyone to modify the code.
operating system
The instructions that the computer uses to tell itself how it "operates". It's the answer to "Who am I and what can I do?"
optical codes
Printed bar codes on products, envelopes, etc.
optical mark recognition
Machine reads special marks, for example to score a test
optical character recognition
Program that uses a machine to recognize the shapes of letters and characters. In the past special shapes had to be used that the computer could recognize. Modern OCR programs can recognize standard fonts very accurately.
optical disk
A storage medium which uses tiny lasers to create peaks and valleys in a plastic layer on a circular disk
optical card
Embedded data on a card. May not be updatable.
Direction the printed page runs: portrait or landscape
An operating system by IBM
Data has been processed and the results (output) are sent to an output device for printing or display.
When typing replaces existing text.

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page scanner
Device that captures a whole page and convert it to digital image
page printer
Printer that uses toner and a heat bar to form characters, like a copy machine.
page out
Moving data from main memory to virtual memory
page setup
How the page is arranged - margins, orientation, header, footer
painting program
A graphics program that deals with images on a dot-by-dot basis. Each pixel is defined separately. Required for photos. Formats include bmp, gif, jpg, pcx, png, tiff, tga and many more.
A display of the available choices, usually with pictures
parallel printer cable
Sends data 8 bits at a time. Printer must be within 50 feet of the computer.
A method of checking for errors in digital data. In an even parity system an extra bit (making a total of 9 bits) is assigned to be on or off so as to make the number of on bits even. In an odd parity system the number of on bits would have to be odd. If the number of on bits is wrong, an error has occurred
A portion of a hard disk. Disks are partitioned in order to reduce cluster size or to have separate partitions for different operating systems.
A secret code used to validate user's identity
Place clipboard contents at cursor location
A list of locations for the computer to look for commands if the full path is not given.
Personal Computer
PCI slot
Newer type of slot on motherboard for peripheral device boards
Personal Digital Assistant. Small personal computer with limited capabilities.
pen input
A pen-like device used to control mouse motions, enter data by drawing letters, or give commands by using set gestures. Esp. used on PDAs.
peripheral device
A device that connects to the motherboard. Includes monitor, mouse, keyboard, modem. etc.
What you are allowed to do. Your user account comes with certain permissions, which allow or disallow certain actions. Unless you have adminsitrator permissions, you will not be able to install new software or update existing software.
personal computer (PC)
Computer for personal use which comes in a variety of shapes and sizes, from tiny PDAs (personal digital assistant) to hefty towers
Personal Information Management (PIM)
A special kind of database for recording appointments, addresses, phone numbers, tasks.
Trying to trick you into revealing personal information like your bank account numbers, Social security numbers, and passwords.
Chemical used by CRT monitors to produce an image.
One dot on a screen. From "picture element".
plasma screen
Screen type used for very large screen involving a gas plasma for creating characters.
A shape on the screen that show where you mouse click will be applied.
pointing stick
A small joystick with a rubbery cap like an eraser on a keyboard. Used in place of a mouse for moving the pointer on the screen.
point size
Measures the height of letters where one point is 1/72 inch
point-of-sale terminal
A special-purpose terminal. Replaces cash register.
Orientation for a document where the width is narrower than the height.
Power On Self Test. Set of basic test of hardware run when a computer is turned on.
power button
On/off switch for your computer
power supply
Converts the electricity from the wall outlet into the flavor that the computer can digest
power spike
A huge jump that lasts for fractions of a second.
power surge
More electricity through the line than normal for several seconds
Pages per minutes. Measures printer speed
presentation graphics
Program which links together a sequence of slides containing text and graphics, for example for a sales presentation or training
primary storage
Main memory, which holds what is currently being processed.
Putting the document on paper with a printer
print preview
Displays how the document will print as opposed to how it looks on the screen
printer resolution
A measure of print quality. Measured in dots per inch (dpi)
print spool
A temporary file created to hold print jobs so user can continue working while printer is printing
Taking data and doing things with it. It is the "thinking" that the computer does - the calculations, comparisons, and decisions
processor speed
Measure of how fast a CPU processes data
A set of detailed directions telling the computer exactly what to do
Writes the actual code for a computer program
Unique to a given manufacturer
PS/2 port
Small connection port used by some mice and keyboards. Computer MUST be off to connect or disconnect at this port.

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a way to arrange records in a particular kind of order or to show only the records that match certain criteria
The set of print jobs waiting to be done

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Random Access Memory (RAM)
Main memory. Volatile memory that is erased when power is turned off.
A file that has been set to Read-Only cannot be modified. After changes, it can be saved with a new name.
Read Only Memory (ROM)
Memory which cannot be changedby the user. Contains the minimum instructions to start the computer. This can be updated with a new version from the manufacturer, with care.
Read The Fine Manual
Device which displays computer output. Short for "computer screen" or "display screen"
read/write head
The device that reads data from a magnetic disk and write data to the disk. It hovers barely over the surface of the platters in a hard disk.
A related set of data which are contained in fields
recording density
How close together bits can be on a sector on the innermost track of a storage disk.
refresh rate
How often the picture is redrawn on a CRT monitor.
registration code
A special code that identifies you as a legal purchaser of software or hardware
relational database
A database composed of linked tables which have records which are made up of fields. No one table has all the information about a record.
removable media
Storage media that are removed from the computer, such as floppy diskettes, tapes, CD-ROM disks
Replace specific word(s) or character(s) with stated text
reset button
Used to restart the computer quickly
response time
How long it takes the computer to respond when data is entered
reverse video
Highlights selected text with a background color and a change of text color.
CD disk which can be erased and written on again.
RGB color system
Red, green, blue dots on a standard monitor screen can create all the colors by combining what dots are aglow.
ribbon cable
A wide flat connection cable. Used for connecting drives to the motherboard or controller card
ring configuration
Network configuration where devices are connected in a ring.
root directory
Area on storage disk that lists where things are on the disk. Names as in A:\ or C:\
rotational delay
Time to rotate a storage disk under the read/write head of the drive to the correct sector. Measured in milliseconds (ms).
Connects several networks and controls the traffic of data among the networks
A horizontal set of cells in a spreadsheet or table
Read The Fine Manual
(What all tech support people want to say to those with tech trouble!)

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Record a file to storage.
Device which displays computer output. Short for "computer screen" or "display screen" .
screen resolution
Measures how clear and detailed the image is
Computer: small subprogram
Languages: the lettering system for writing a language. Latin script is used by English, German, French, Italian, and Spanish. Cyrillic script is used by Russian, Bulgarian, Serbian, and other Slavic languages.
Graphical interface: moving document around within window;
text interface: moving the lines displayed on the screen up or down one line at a time
Look for specific word(s) or character(s) in a document or in a set of files
A numbered wedge-shaped area of a storage disk
security program
A program which protect your computer from malware or other dangers.
seek time
Time it takes to move the read/write head of a drive to the proper track on the storage disk. Measured in milliseconds (ms)
To pick out the object or file or folder that you want the computer to do something with next. Usually you select by clicking on something or dragging across something. The selection is highlighted by changing the colors of what you selected.
Integrated circuit on a chip. This is what modern computers use for memory
Files for printing a single color of a 4 color print job. Needed for professional printing.
serial printer cable
Sends data only 1 bit at a time. Printer can be up to 1000 feet from the computer.
A computer which handles network tasks and data
settling time
Time for read/write head to lower to the storage disk and cease vibrating, allowing reliable reading and writing. Measured in milliseconds (ms)
Background color or pattern
Allow other computers on the network to view or use a file or device.
Software which you may try for a limited time before purchasing
An icon that opens a program or file when you double-click it.
shut down
Close all background programs and turn off computer
single sheet paper
Regular letter paper
single-sided disk
Only one surface of the storage disk is used.
slack space
Unused space in a cluster beyond the data stored in it.
A single picture or screen in a sequence for a presentation
slide show
A sequence of slides that can play automatically or in response to a click.
smart phone
A cell phone that is more than just a phone. It generally has a camera, GPS, and can browse the web and download apps. The screen is larger than a standard cell phone.
smart terminal
Also called intelligent or programmable. Can process or store data on its own.
smart card
Credit card type card which has an embedded computer chip that updates your account values with each use.
A slot on the motherboard for an expansion card to plug in.
soft copy
Displayed on screen or by other non-permanent means
The programs (instructions) that tell the computer what to do
Solid State Drive (SSD)
A storage device that uses flash memory or DRAM to store data electronically. Flash memory keeps the data when power goes off. DRAM memory loses the data when the power goes off.
source code
The underlying code a computer program or a web page.
Space between letters or lines of text
speech recognition
Process by which a computer takes what you speak and uses it.
speaker dependent system
A voice input system which must be trained to recognize each word by each individual user.
speaker independent system
A voice input system which recognizes words from most speakers with no training.
spell checker
Program which looks for spelling errors
See power spike
Program for handling numeric data, like budgets, financial statements, grade sheets, and sales records
A program that records what you do on your computer and/or where you go on the Internet. It records your logins and passwords.
Structured Query Language - the language for commands that create database queries
Software that does not need other programs in order to work correctly.
star configuration
Network configuration where all devices are connected directly to the host computer
Start menu
On Windows, the menu that opens from the Start button at the bottom left of the screen or from the Windows key.
The media and methods used to keep information available for later use
A step in the Machin Cycle where the processor puts the current value in a memory location.
Style set: A combination of properties that is saved so it can be easily applied again.
Style (old usage): Bold, italics, underline etc.
style sheets
Sets of formats saved to reuse.
A pen-type device that lets you 'write' on a tablet or screen to communicate with the computer.
A set of separate applications which are packaged together usually at a lower price than they would cost separately. Also may have some additional software to help the programs work together.
Used for weather forecasting, engineering design and testing, serious decryption. They cost several million dollars so they are few and far between.
See power surge
surge protector
Device that blocks power spikes
Super VGA, a video type allowing several large resolutions and 16 million colors.
swap file
File used for virtual memory in Windows
Moving data from main memory to virtual memory and back
system clock
Electronic pulse used to synchronize processing. Measured in megahertz (MHz)
system software
Programs that handle the running of your computer's hardware and communication with your programs.
system requirements
Hardware needed to run the program
systems analyst
Designs the overall program requirements and sets the strategy for the program.

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A set of rows and columns
A small computer about the size of a small notebook. Often comes with a stylus for writing on the screen. Does not have an included DVD drive or much storage for files. Does not substitute fully for a laptop or desktop computer.
A code element in an HTML document that creates a part of a document, like a paragraph, heading, table, or image. Most tags come in pairs, an opening tag and a closing tag, like <p> and </p> for a paragraph. The text to display goes between the tags.
Any long-distance communications, especially television
Accessing computer files located elsewhere
A pre-designed document that can be used to create a new document.
terabyte (TB)
1 TB = 1000 GB (gigabytes)
A keyboard and computer screen. Also called display terminal or video display terminal (VDT)
terminal emulation
Mimicking a different kind of computer terminal
text interface
User interface that uses only text commands, no graphics.
thermal printer
Printer that uses heat on chemically treated paper to form characters, like some fax machines.
Contains synonyms for selected word
thin client
A computer that connects to a network but which has little computing power of its own. Most of the work is done by the network servers.
How much data is moved in a certain amount of time. Usually measured in kilobytes per second (Kbps) or megabytes per second (Mbsp)
time slice
Minimum amount of time for a task in the CPU. Measured in milliseconds (ms)
Multiple users share use of the host computer processor
token ring configuration
Network configuration where devices are connected in a ring and a token is passed around the ring to handle the turns of access to the communications line
A touch sensitive pad for controlling pointer motion. Click by tapping the pad. Popular for laptop computers.
Computer screen that reacts to being touched by finger.
Vertical case for a personal computer
A circular ring around one side of a storage disk.
track sector
The area of intersection of a track and a sector on a storage disk
An input device similar to a mouse except the ball is on top where it can be moved with only one finger or the thumb.
tractor feed
Uses sprockets to pull continuous-feed paper through a printer
transcription error
Typing the wrong character like typing 7754 instead of 7154.
transition effect
A change that happens when a new slide appears in a presentation. The new slide might appear to fly in from the side or reveal itself in strips or some other fancy effect.
transmission media
The physical materials that are used to transmit data between computers
transmission rate
Rate data is transferred.
digital: Measured in bits per second (bps)
analog: Measured in baud where one baud is one change in the signal per second.
transmission protocol
Rules for what information is exchanged and in what order
transposition error
Interchanging two characters like typing 7754 instead of 7745.
Software that allows you to try it out before buying. After a set amount of time or a set number of minutes of use, the trial will expire. The program may quit running at all or may drop down to a limited number of features.
(short for Trojan horse) A program that does not appear to be destructive but which, in fact, allows others to access your data, to record your logins and passwords, or to destroy or alter your data. 
A set of lessons that walks you through the use of hardware or software
twisted wire
Phone line, consisting of 4 twisted pairs of wires bound together
A set of characters of similar design
typical install
A choice offered when installing a program. Installs only the features that the author expects most people to want.

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Reverses whatever change you just made
Unicode Worldwide Character Standard. A scheme for encoding characters using 16 bits per character. Unicode includes glyphs for the scripts for all major languages, including symbols.
Operating system developed first for scientific applications by Bell Labs. It now comes in various flavors for different purposes.
unused storage
Part of Main Memory that is not yet used. You need a certain amount of elbow room to avoid slow processing and even errors.
To replace a program with a newer version of one you already have
Transfer a file from your computer to another
Uninterruptable Power Supply - combination of surge protector, power line conditioner, and battery power supply
Universal Serial Bus. A type of connection that can be used by a wide range of devices, rather than each device having its own shape for its connector. Fast (12 Mbps). Quickly replacing serial and parallel ports.
USB drive
A small, thumb-size storage device that connects to the computer with a USB connector. Also called a thumb drive, jump drive, and many other names.
USB hub
A USB device with several USB ports on it. Hub can be daisy-chained (linked in a chain) as long as the total power needed for all devices running at once is not too high.
user interface
The way the user tells the software what to do and how the computer displays information and options to the user.
user friendly
A program or user interface which is easy to use
user response
What the user does to answer a question that the computer asks
user ID, user name
Identification name of user when completing an login dialog.
user profile
A set of preferences for a particular user. Available in network settings.
utility program
A program that performs tasks related to the maintaining of your computer's health - hardware or data.

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vacuum tube
Oldest device used for memory in electronic computer. Generated a lot of heat and burned out often.
Photo Credit: Copyright (c) 123RF Stock Photos
A means of defining an image in terms of geometric shapes. Used by drawing programs
The particular edition of the program. Different versions may have slight differences or be vastly changed. A program usually requires a different version for each operating system that it will be installed in.
Video Graphics Adapter - low end video type with 640 x 480 resolution and 256 colors
A motion picture recording. Can be on tape or digital.
video camera
Records data on tape or digital media that can be uploaded to the computer
video conference
Connecting to other people with live video of all people in the conversation. This can substitute for a face-to-face meeting.
video display terminal (VDT)
Device which displays computer output. From early network terminals.
video display unit (VDU)
Any device that displays computer output including on hand-held devices.
Not really there but acts as though it were real
virtual memory
Disk space used as part of main memory
virtual machine
Method that lets you run a separate operating system in a window without having to shut down your normal operating system. You can run programs in that window that won't run on your usual operating system.
A computer program that performs tasks without your permission or consent. May be harmless but annoying or may be highly damaging.
voice input
Using human voice to directly enter data or commands
Term for memory which loses data when the power goes off.

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Wide Area Network - a network of computers that are far apart, as in different cities or countries
warm boot
Method of restarting the computer which doesn't require the hard disk to stop spinning first.
A video camera that connects directly to a computer. It is used to stream live video to a web site, a video phone call, like Skype, or video conferencing.
A rectangular area of the screen which displays a program's user interface, a document, or a system message
An operating system from Microsoft that comes in many different versions. It uses a graphical interface and put programs in a rectgular 'window' on the screen.
word wrap
Automatically wrapping the text to the next line so it all fits within the width of the screen, window, or paper page.
word processing
A computer program used to create documents which are text-based, like letters, memos, and term papers. It is the most used computer application.
Amount of data the CPU can process at one time. Measured in bits.
working storage
Temporary storage of the intermediate results of work in progress
Computer networked to other computers. Sometimes more capable than a desktop model.
Write Once Read Many. Most common type of optical disk
An unwanted computer program that duplicates itself across a computer network. It uses up the network's storage space and resources and can interfere with the ability of the network to function at all.
write protect
Method that keeps data from being over-written. May be a physical obstacle or a file attribute choice that prevents overwriting.
What You See Is What You Get (pronounced "wiz-e-wig")- how a page displays on screen is the same as how it prints

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A computer that has been taken over by malware to perform tasks like sending spam or phishing emails, click fraud, or denial of service attacks. The computer's owner is often not aware of what the computer is doing unless the Internet connection slows to a crawl.
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