Glossary
|
|
Chapter 2
|
|
64-bit processor
| A microprocessor with registers, address bus, and a data bus that hold 64 bits of data, in contrast to 32-bit processors that hold 32 bits of data
|
Access time
| The estimated time for a storage device to locate data on a disk, usually measured in milliseconds
|
All-in-one computer
| A desktop computer form factor in which the system unit and touchscreen are integrated into a single unit
|
Benchmarks
| A set of tests used to measure computer hardware or software performance
|
BIOS
| A small set of basic input/output system instructions stored in ROM
|
Blu-ray
| A high-capacity storage technology that stores up to 25 GB per layer on Blu-ray discs (BDs)
|
Blue screen of death
| An error condition in which a PC "freezes" and displays a black screen (blue screen prior to Windows Vista); usually turning the computer off and turning it on again clears the error
|
Bootstrap loader
| A program that automatically runs when a computer is first turned on in order to load the operating system
|
Capacitors
| Electronic circuit components that store an electrical charge; in RAM, a charged capacitor represents an "on" bit, and a discharged one represents an "off" bit
|
Card reader
| A device that can be used to read and record data on solid stage storage devices, such as flash memory cards
|
CD
| (Compact Disc) An optical storage medium used to store digital information. CD-ROMs are read only. CD-Rs and CD-RWs can be used to record data.
|
CISC
| (Complex Instruction Set Computer) A general-purpose microprocessor chip designed to handle a wider array of instructions than a RISC chip
|
Color depth
| The number of bits that determines the range of possible colors that can be assigned to each pixel. For example, an 8-bit color depth can create 256 colors.
|
CPU cache
| Special high-speed memory providing the CPU rapid access to data that would otherwise be access from disk or RAM
|
Data bus
| An electronic pathway or circuit that connects the electronic components (such as the processor and RAM) on a computer's motherboard
|
Data transfer rate
| The amount of data that a storage device can move from a storage medium to computer memory in one time unit, such as one second
|
Dedicated graphics
| Circuitry for graphics that is supplied on an expansion card rather than integrated into the main system board of a digital device
|
Desktop computer
| A computer that is small enough to fit on a desk and built around a single microprocessor chip
|
Dot matrix printer
| A printer that creates characters and graphics by striking an inked ribbon with small wires called "pins," generating a fine pattern of dots
|
Dot pitch
| (dp) The diagonal distance between colored dots on a display screen. Measured in millimeters, dot pitch helps to determine the quality of an image displayed on a monitor.
|
Double layer DVD
| A DVD that essentially stacks data in two different layers on the disk surface to store 8.5 GB, twice the capacity of a standard DVD.
|
Drive bays
| Areas within a computer system unit that can accommodate additional storage devices
|
Duplex printer
| A printer that prints on both sides of the paper in a single pass
|
Duty cycle
| A measurement of how many pages a printer is able to produce per day or month
|
DVD
| (Digital Video Disc or Digital Versatile Disc) An optical storage medium similar in appearance and technology to a CD but with higher storage capacity
|
DVI
| (Digital Visual Interface) A standard type of plug and connector for computer display devices
|
Dynamic RAM
| (DRAM) Random access memory that requires a power source to hold data; used as main memory on most computers
|
EEPROM
| (Electrically Erasable Programmable Read-Only Memory) A type of non-volatile storage typically used in personal computers to store boot and BIOS data
|
Enhanced media player
| Handheld devices designed to play music, but with enhanced features, such as a browser and apps
|
eSATA
| A standard for high-speed ports, plugs, and connectors typically used to connect external hard drives to computers
|
Expansion bus
| The segment of the data bus that transports data between RAM and peripheral devices
|
Expansion card
| A circuit board that is plugged into a slot on a computer motherboard to add extra functions, devices, or ports
|
Expansion port
| A socket into which the user plugs a cable from a peripheral device, allowing data to pass between the computer and the peripheral device
|
Expansion slot
| A socket or "slot" on a PC motherboard designed to hold a circuit board called an expansion card
|
FireWire
| A standard for fairly high-speed ports, plugs, and connectors typically used to connect external storage devices, and for transferring data from cameras to computers
|
Floppy disk
| A removable magnetic storage medium, typically 3.5" in size, with a capacity of 1.44 MB.
|
Form factor
| The configuration of a computer's system unit; examples include tower, mini-tower, and cube
|
Front side bus
| (FSB) The data bus that carries signals between the CPU and RAM, disks, or expansion slots
|
Game controllers
| Devices such as joysticks wands, and steering wheels, used to control on-screen action in computer games
|
Gigahertz
| (GHz) A measure of frequency equivalent to one billion cycles per second
|
Graphics card
| A circuit board inserted into a computer to handle the display of text, graphics, animation, and videos. Also called a video card or graphics board.
|
Graphics processing unit
| (GPU) A microprocessor dedicated to rendering and displaying graphics on personal computers, workstations, and videogame consoles
|
Hard disk drive
| A computer storage device that contains a large-capacity rigid storage surface sealed inside a drive case. Typically used as the primary storage device in personal computers.
|
Hard disk platter
| The component of a hard disk drive on which data is stored. It is a flat, rigid disk made of aluminum or glass and coated with a magnetic oxide
|
HDMI
| (High-Definition Multimedia Interface) A standard type of plug and connector for computer display devices
|
Head crash
| A collision between the read-write head and the surface of the hard disk platter, resulting in damage to some of the data on the disk
|
Home computer system
| A personal computer designed for use with mainstream computer applications such as Web browsing, e-mail, music downloads, and productivity software
|
Hot-plugging
| The ability of a component, such as a USB flash drive, to connect or disconnect from a computer while it is running; Also referred to as hot-swapping
|
Ink jet printer
| A non-impact printer that creates characters or graphics by spraying liquid ink onto paper or other media
|
Integrated graphics
| Circuitry for graphics processing that is integrated into the mainboard rather than as an expansion card
|
Lands
| Non-pitted surface areas on a CD that represent digital data. (See also pits.)
|
Laptop Computer
| A small, lightweight, portable computer that usually runs on batteries. Sometimes called a notebook computer.
|
Laser printer
| A printer that uses laser-based technology, similar to that used by photocopiers, to produce text and graphics
|
LCD display
| (Liquid Crystal Display) Technology used for flat panel computer screens typically found on notebook computers
|
LED display
| (Light-Emitting Diode display) A display device that either uses LEDs to produce an image on the screen, or and LCD display that uses LEDs as backlighting
|
Linux platform
| A computer that is running the Linux operating system
|
Mac platform
| A family or category of Macintosh-compatible personal computers designed and manufactured by Apple Computer
|
Magnetic storage
| A technology for recording data onto disks or tape by magnetizing particles of an oxide-based surface coating
|
Megahertz
| (MHz) A measure of frequency equivalent to one million cycles per second
|
Memory card
| A small, flat, solid state storage medium, frequently used to store data on cameras and handheld devices
|
Microprocessor clock
| A timing signal that sets the pace for executing instructions in a microprocessor
|
Mouse
| An input device that allows the user to manipulate objects on the screen by clicking, dragging, and dropping
|
Multi-core processor
| A microprocessor that contains circuitry for more than one processing unit
|
Non-volatile
| Any electronic component that does not require a constant supply of power to hold data
|
Optical storage
| A technology that records data as light and dark spots on a CD, DVD, or other optical media
|
Overclocking
| Forcing a computer component, such as a microprocessor, to run at a higher speed than intended by the manufacturer
|
Parallel processing
| The simultaneous use of more than one processor to execute a program
|
PC platform
| A family of personal computers that use Windows software and contain Intel-compatible microprocessors
|
Peripheral device
| A component or equipment, such as a printer, that expands a computer's input, output, or storage capabilities
|
Pipelining
| A technology that allows a processor to begin executing an instruction before completing the previous instruction
|
Pits
| Spots on a CD that are "burned" onto an optical storage medium to represent digital data
|
Pixels
| (Short for picture element) The smallest unit in a graphic image. Computer display devices use a matrix of pixels to display text and graphics.
|
Pointing device
| An input device, such as a mouse, trackball, pointing stick, or trackpad, that allows users to manipulate an on-screen pointer and other screen-based graphical controls
|
Portable computer
| Any type of computer, such as a notebook computer, that runs on batteries and is designed to be carried from one location to another; also called a mobile computer
|
PostScript
| A printer language, developed by Adobe Systems, which uses a special set of commands to control page layout, fonts, and graphics
|
Power surge
| A spike in electrical voltage that has the potential to damage electronic equipment such as computers
|
Printer Command Language
| (PCL) A standard for formatting codes embedded within a document that specify how a printer should format each page
|
RAM
| (Random Access Memory) Computer memory circuitry that holds data, program instructions, and the operating system while the computer is on
|
Random access
| The ability of a storage device (such as a disk drive) to go directly to a specific storage location without having to search sequentially from a beginning location
|
Read-only technology
| Storage media that can only be read from, but not recorded on
|
Read-write head
| The mechanism in a disk drive that magnetizes particles on the storage disk surface to write data, or senses the bits that are present to read data
|
Recordable technology
| The devices and standards that allow computers to write data permanently on CDs and DVDs, but does not allow that data to be changed once it has been recorded
|
Response rate
| In relation to display technology, response rate is the time it takes for one pixel to change from black to white then back to black
|
Rewritable technology
| The devices and standards that allow users to write data on a storage medium and then change that data
|
RISC
| (Reduced Instruction Set Computer) A microprocessor designed for rapid and efficient processing of a small set of simple instructions
|
ROM
| (Read-Only Memory) Refers to one or more integrated circuits that contain permanent instructions that the computer uses during the boot process
|
Safe Mode
| A menu option that appears when Windows is unable to complete the boot sequence. By entering Safe Mode, a user can gracefully shut down the computer, then try to reboot it.
|
Screen resolution
| The density of the grid used to display text or graphics on a display device; The greater the horizontal and vertical density, the higher the resolution
|
Sequential access
| A characteristic of data storage, usually on computer tape, that requires a device to read or write data one record after another, starting at the beginning of the medium
|
Serial processing
| Processing of data one instruction at a time, completing one instruction before beginning another
|
Smartphone
| A cellular phone that has a high resolution, color screen, a browser, and the ability to run apps
|
Solid state drive
| Data storage device that utilizes erasable, rewritable circuitry
|
Solid state storage
| A technology that records data and stores it in a microscopic grid of cells on a non-volatile, erasable, low-power chip
|
Storage density
| The closeness of the particles on a disk surface. As density increases, the particles are packed more tightly together and are usually smaller.
|
Storage device
| A mechanical apparatus that records data to and retrieves data from a storage medium
|
Storage medium
| The physical material used to store computer data, such as a floppy disk, a hard disk, or a CD-ROM
|
Surge strip
| A device that filters out electrical spikes that could damage computer equipment
|
System unit
| The case or box that contains the computer's power supply, storage devices, main circuit board, processor, and memory
|
Tablet computer
| A small, portable computer with a touch-sensitive screen that can be used as a writing or drawing pad
|
Thunderbolt
| A high-speed expansion port typically used to connect external storage devices to a computer
|
Touch screen
| A display device that accepts input from being touched with a stylus or fingertip
|
Tower case
| A desktop computer form factor that stores the system board and storage devices in a tall system unit with detached display and keyboard
|
Trackpad
| A touch-sensitive surface on which you slide your fingers to move the on-screen pointer
|
UPS
| (Uninterruptible Power Supply) A battery-backed device designed to provide power to a computer during blackouts, brownouts, or other electrical disruptions
|
USB
| (Universal Serial Bus) A high-speed bus commonly used for connecting peripheral devices to computers
|
USB flash drive
| A portable solid state storage device nicknamed "pen drive" or "keychain drive" that plugs directly into a computer's USB port
|
USB hub
| A device that provides several auxiliary USB ports
|
VGA
| (Video Graphics Array) A screen resolution of 640 x 480
|
Viewing angle width
| The angle at which you can clearly see the screen image from the side
|
Virtual keyboard
| A keyboard that is displayed on a touch screen and used for input on smartphones and tablet computers
|
Virtual memory
| A computer's use of hard disk storage to simulate RAM
|
Volatile
| A term that describes data (usually in RAM), which can exist only with a constant supply of power
|
Word size
| The number of bits that a CPU can manipulate at one time, which is dependent on the size of the registers in the CPU, and the number of data lines in the bus
|