Glossary of Western Digital Hard Disk Drive (Letter E)

EasyLink™
A WD utility that allows users to locate and set up a drive as a local drive from any computer quickly and easily.

ECC
Error correction code. A mathematical algorithm that detects and corrects data errors.

ECC on the fly
A hardware correction technique that corrects errors in the read buffer before host transfer and without any performance penalties. These error corrections are invisible to the host system because they do not require assistance from drive firmware.

EESA
Enterprise extensions S.M.A.R.T. accessed. An expanded command set that provides SCSI-like control for server environments, optimizing operation and performance when drives are used in vibration-prone multidrive systems such as rack-mounted servers.

EIDE
Enhanced Integrated Drive Electronics. See PATA

embedded servo control
A design that generates accurate feedback to the head position servo system without requiring a full data surface, because servo control data is stored on every surface (unlike dedicated servo control).

encoding
A process of modifying data patterns before writing them onto a disk surface.

enterprise
Series of computers employed largely in high-volume and multiuser environments such as servers or networking applications; may include single-user workstations required in demanding design, engineering, and audio/video applications.

error log
A record that contains error information.

error rate
The number of errors of a given type that occur when reading a specified number of bits.

ESD
Electrostatic Discharge. Rapid discharge of static electricity that can damage integrated circuits in computers and communications equipment. ESD prevention is aided by such items as ESD wrist straps and ESD hard drive bags.

Ethernet
A standard method of connecting computers to a Local Area Network (LAN) using coaxial cable, twisted pair, and fiber optic wiring standards.

extended partition
A partition on a disk where non-system files (other than DOS or operating system files) can be stored. Multiple partitions can be created on a hard disk: one primary partition and one or more extended partition(s). Operating system files must reside on the primary partition; logical drives can be created on an extended partition.