Glossary 305heat sink — A metal plate on some processors that helps dissipate heat.hibernate mode — A power management mode that saves everything in memory to areserved space on the hard drive and then turns off the computer. When you restartthe computer, the memory information that was saved to the hard drive isautomatically restored.HTTP — hypertext transfer protocol — A protocol for exchanging files betweencomputers connected to the Internet.Hyper-Threading — Hyper-Threading is an Intel technology that can enhance overallcomputer performance by allowing one physical processor to function as two logicalprocessors, 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).IIC — integrated circuit — A semiconductor wafer, or chip, on which thousands ormillions of tiny electronic components are fabricated for use in computer, audio, andvideo equipment.IDE — integrated device electronics — An interface for mass storage devices in whichthe 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 digitalcameras and DVD players, to the computer.infrared sensor — A port that allows you to transfer data between the computer andinfrared-compatible devices without using a cable connection.integrated — Usually refers to components that are physically located on thecomputer’s system board. Also referred to as built-in.I/O — input/output — An operation or device that enters and extracts data from yourcomputer. Keyboards and printers are I/O devices.I/O address — An address in RAM that is associated with a specific device (such as aserial connector, parallel connector, or expansion slot) and allows the processor tocommunicate with that device.IrDA — Infrared Data Association — The organization that creates internationalstandards for infrared communications.IRQ — interrupt request — An electronic pathway assigned to a specific device sothat the device can communicate with the processor. Each device connection must be
