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L___________________________
L-cable
A 110-wire cable used for 32-bit SCSI-3 buses.
L2 Cache
Level 2 Cache. Memory cache that is between the CPU and the main memory (level 1 cache is a memory cache that is onboard the CPU chip itself). L2 cache can provide faster CPU access to instructions and data in memory, thus increasing system performance.
LADDR
Layered Device Driver. A SCSI device driver architecture used in early versions of OS/2.
Lead-In
An area at the beginning of each session on a recordable compact disc which is left blank for the session's Table of Contents (track numbers and start-and-stop points) and other miscellaneous information about the disc and about the recorded tracks. The lead-in is written when a session is closed, and takes up 4500 sectors on disc (1 minute, or roughly 9 megabytes). The lead-in also indicates whether the disc is multisession and, if the disc is not closed, which is the next recordable address on the disc.
Lead-Out
An area at the end of a session which indicates that the end of the data has been reached; there is no actual data written in the lead-out. The first lead-out on a disc is 6750 sectors (1.5 minutes, about 13 megabytes) long; any subsequent lead-outs are 2250 sectors (.5 minute, about 4 megabytes).
LED
Light-Emitting Diode. Used for display in some electronic devices.
Link
To produce an executable program from compiled modules (programs, routines,libraries) by merging the object code and resolving interconnecting references.
Link Area or Link Blocks
See Run-in/Run-out Blocks below.
Link Layer
The lowest layer of the Internet Protocols, concerned with the physical interconnection of computers.
Linked Multisession
A disc containing more than one session, in which all of the data in the various sessions on disc can be seen as if it had all been recorded in one single, large session. To link sessions in Easy-CD Pro 95, you must check a box in the Load Contents tab. In Easy-CD Pro for Windows 3.1, use Load Contents.
LKM
A loadable kernel module, software which runs in kkernel space, but which can be loaded separately after the system is running.
Local Bus
A computer bus that allows devices to transfer data directly to the CPU.VL-Bus and PCI are common types of local bus.
Logical Block
The smallest addressable space on a disc. Each logical block is identified by a unique Logical Block Number (LBN), assigned in order starting from 0 at the beginning of the disc. Under the ISO 9660 standard, all data on a CD is addressed in terms of Logical Block Numbers. At present, CD recording is supported at one Logical Block per logical sector.
Logical Format/Logical Structure
A logical file format such as ISO 9660 translates the sector-by-sector view of a compact disc into a virtual "tree" of directories and files, which makes it easier for both humans and computers to use the information on the disc.
Logical Unit
A subdivision, either logical or physical, of a SCSI device (actually the place for the device on the SCSI bus). Most devices have only one logical unit, but up to eight are allowed for each of the eight possible devices on a SCSI bus.
Logical Unit Number
See LUN.
Low-level Format
The process of writing special markers and other tracking information on a storage medium such as a floppy disk or hard disk.
LUN
Logical Unit Number. A 3-bit value (zero to seven) identifying a logical unit in a device.
Linux
Linux is a free Unix-type operating system originally created by Linus Torvalds with the assistance of developers around the world. Linux is an independent POSIX implementation and includes true multitasking, virtual memory, shared libraries, demand loading, proper memory management, TCP/IP networking, and other features consistent with Unix-type systems. Developed under the GNU General Public License, the source code for Linux is freely available to everyone.
There are many different Linux distributions, or versions. A "distribution" is the compiled Linux source code, usually combined with extra features and software. Some distributions are available for download at no charge while others are available at affordable prices on CD-ROM from Linux retailers worldwide.
Each distribution has its own purpose, and a number of factors should go into deciding which distribution is best for each user. Some distributions are better suited to home users, others are excellent for commercial settings. Some are better suited for Intel or Macintosh PCs, other are excellent for use on high-performance computers. For more information you can visit
LVDlink
Low Voltage Differential Link allows greater Ultra2 SCSI device connectability and longer SCSI cables. LVDlink lowers the amplitude of noise reflections and allows higher transmission frequencies.
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