2009

Qualification The process by which sample components are tested for their compatibility and utility as parts of a system. Western Digital OEM customers qualify WD hard drives for use in their computers. Queue A first-in-first-out (FIFO) data structure used to sequence multiple demands for a resource such as a printer, processor, or communications channel.…

Partition A way to logically divide a hard drive so that an operating system treats each partition as a separate hard drive. Each partition has a unique drive letter. Passive Termination A termination architecture that is used to match the impedance at the end of the SCSI bus by using a voltage divider network of passive resistors.…

Operating System Software that allows the user and programs installed on your system to communicate with computer hardware such as a hard drive. Original Equipment Manufacturer (OEM) In the case of Western Digital, OEM customers are companies such as Compaq, Gateway, IBM and Dell.…

Network Computer A kind of computer that contains limited data storage capacity and is used to communicate with a central data storage facility such as a server or RAID system.…

Magnetic flux The pattern of magnetic pole directions of the bits written on the disk. Manufacturing Yield The portion of unit production of a manufacturing process that is usable, saleable product; usually expressed as a percent of total output of that product.…

Landing Zone The heads move to this location on the inner portion of the disk when commanded, or when the power has been turned off. User data is not stored in this area of the disk. Laser Textured Media Laser textured disks minimize the wear and friction on a hard drive.…

Kilobyte (KB) Usually, this is a unit of 1000 bytes. In the case of computer memory, which is partitioned into sizes that are a power of two, a kilobyte is equal to 2 10 or 1024 bytes.…

Jumper In EIDE drives, a jumper is an electrically-conductive component that you place over pairs of pins that extend from the circuit board on the hard drive jumper block to connect them electronically. For example, a jumper is one way to designate a hard drive as master or slave.…

IDE (Integrated Drive Electronics) A type of drive where the interface controller electronics are incorporated into the design of the hard drive rather than as a separate controller. Index Pulse Signal A digital pulse signal indicating the beginning of a disk revolution.…

Half-Duplex A communications protocol that permits transmission in both directions but in only one direction at a time. Half-height Drives Standard 3.5-inch hard drives are available in heights of 1.0-inch and 1.6-inches. Half-height drives measure 1.6-inches in height. Hard Drive An electromechanical device used for information storage and retrieval, incorporating one or more rotating disks on which data is recorded, stored and read magnetically.…