Dell Precision 490 - Manual (Page 110)

H
hard drive — A drive that reads and writes data on a hard disk. The terms hard drive and hard disk are often used interchangeably.
heat sink — A metal plate on some processors that helps dissipate heat.
help file — A file that contains descriptive or instructional information about a product. Some help files are associated with a particular program, such as Help in
Microsoft Word. Other help files function as stand-alone reference sources. Help files typically have a filename extension of .hlp or .chm.
hibernate mode — A power management mode that saves everything in memory to a reserved space on the hard drive and then turns off the computer.
When you restart the computer, the memory information that was saved to the hard drive is automatically restored.
HTML — hypertext markup language — A set of codes inserted into an Internet web page intended for display on an Internet browser.
HTTP — hypertext transfer protocol — A protocol for exchanging files between computers connected to the Internet.
hyper-threading — Hyper-Threading is an Intel® technology that can enhance overall computer performance by allowing one physical processor to function as
two logical processors, capable of performing certain tasks simultaneously.
Hz — hertz — A unit of frequency measurement that equals 1 cycle per second. Computers and electronic devices are often measured in kilohertz (kHz),
megahertz (MHz), gigahertz (GHz), or terahertz (THz).
I
IC — Industry Canada — The Canadian regulatory body responsible for regulating emissions from electronic equipment, much as the FCC does in the United
States.
IC — integrated circuit — A semiconductor wafer, or chip, on which thousands or millions of tiny electronic components are fabricated for use in computer,
audio, and video equipment.
IDE — integrated device electronics — An interface for mass storage devices in which the controller is integrated into the hard drive or CD drive.
IEEE 1394 — Institute of Electrical and Electronics Engineers, Inc. — A high-performance serial bus used to connect IEEE 1394-compatible devices, such as
digital cameras and DVD players, to the computer.
infrared sensor — A port that allows you to transfer data between the computer and infrared-compatible devices without using a cable connection.
integrated — Usually refers to components that are physically located on the computer's system board. Also referred to as built-in.
I/O — input/output — An operation or device that enters and extracts data from your computer. Keyboards and printers are I/O devices.
I/O address — An address in RAM that is associated with a specific device (such as a serial connector, parallel connector, or expansion slot) and allows the
processor to communicate with that device.
IrDA — Infrared Data Association — The organization that creates international standards for infrared communications.
IRQ — interrupt request — An electronic pathway assigned to a specific device so that the device can communicate with the processor. Each device connection
must be assigned an IRQ. Although two devices can share the same IRQ assignment, you cannot operate both devices simultaneously.
ISP — Internet service provider — A company that allows you to access its host server to connect directly to the Internet, send and receive e-mail, and access
websites. The ISP typically provides you with a software package, user name, and access phone numbers for a fee.
K
Kb — kilobit — A unit of data that equals 1024 bits. A measurement of the capacity of memory integrated circuits.
KB — kilobyte — A unit of data that equals 1024 bytes but is often referred to as 1000 bytes.
key combination — A command requiring you to press multiple keys at the same time.
kHz — kilohertz — A measurement of frequency that equals 1000 Hz.
L
LAN — local area network — A computer network covering a small area. A LAN usually is confined to a building or a few nearby buildings. A LAN can be
connected to another LAN over any distance through telephone lines and radio waves to form a wide area network (WAN).
LCD — liquid crystal display — The technology used by portable computer and flat-panel displays.
LED — light-emitting diode — An electronic component that emits light to indicate the status of the computer.
local bus — A data bus that provides a fast throughput for devices to the processor.
LPT — line print terminal — The designation for a parallel connection to a printer or other parallel device.