Computer Industry Acronyms
AC: Alternating Current. Current that reverses direction many times in a second.
ACE: Access Control Entity. An individual entry of the ACL defining a specific object and its security attributes.
ACK: Acknowledgement
ACL: Access Control List. A data token attached to the descriptor of a specific object on the network that defines what users and/or groups are allowed to access that object and what degree of access they are allowed.
ACPI: Advanced Configuration and Power Interface
ACR: Audio Communications Riser. A specialized card that takes the concept of the AMR and adds networking functionality as well.
ADC: Analog to Digital Converter
ADSI: Active Directory Service Interface
AFS: Automatic File Compression. A technology built into NTFS that allows files and directories to be compressed and uncompressed on the fly, as needed.
AGP: Advanced Graphics Port. A high-speed bus designed exclusively for graphics.
AIT: Advanced Intelligent Tape. A tape format that incorporates a linear recording mechanism in conjunction with a memory chip embedded in the tape cartridge to allow for advanced features.
ALDC: Adaptive Lossless Data Compression. An advanced data compression algorithm that allows a greater degree of compression without any loss of data.
ALU: Arithmetic Logic Unit. The subcomponent of a CPU that handles rudimentary mathematical functions.
AMR: Audio Modem Riser. A specialize card found on certain motherboards that supports either a modem, a sound card, or a device that combines both functions.
ANSI: American National Standards Institute. This term refers to an organization charged with establish standards for several different industries, including the computer industry. It also refers to an early character set developed by that organization.
API: Application Programming Interface
API: Application Programming Interface. A collection of files used by Microsoft OSs that maintains and translates the basic command set required by all devices of a particular type.
APM BIOS: Advanced Power Management Basic Input Output Services
Appendix D
ARC: Advanced RISC Computing
ASCII: American Standard Code for Information Interchange. An early character set used by computers.
ASMP: Asymmetric Multiprocessing. The ability of an OS to use more than one processor, where the OS code runs on one processor and all other application code and user data is distributed across the remaining processors.
ASPI: Advanced SCSI Programmer Interface. A two-tied device driver scheme employed by SCSI.
AT: Advanced Technology. A form factor promoted by IBM in the early days of personal computing.
ATA: Advanced Technology Attachment.
ATAPI: Advanced Technology Application Programming Interface. The API than controls IDE devices.
ATAPI: ATA Packet Interface: A device interface that allows data to be transmitted in packets, rather than a byte at a time.
ATX: Advanced Technology extended: An improvement of the older AT form factor that provided greater accessibility to components and far more efficiency in the use of space.
AUI: Attachment Unit Interface: A 15-pin female connector used by some early network cards and sound cards.
BCC: The Block Check Character. Includes error detection and correction data, which may include parity (rarely used these days), checksum (on its way out) or cyclical redundancy check (the most common method in use today).
BDC: Any server on an NT domain that houses a copy of the security database, which is periodically updated by the PDC.
BIOS: Basic Input Output Services. The instruction set on a computer system that provides the startup code along with a number of routines that provide command support for the hardware installed on the system.
BIOS: Basic Input Output System. Basic instruction, usually (but not always) loaded onto a Read Only Memory chip that leads the system through the process of startup and provides instructions as to how to communicate with different forms of hardware.
BNC: Bayonet Neil-Conselman. A barrel-shaped connector named after the two engineers involved in the design.
BRI: Basic Rate ISDN. 2 64K B-channels and 1 16K D-channel.
BSB: Back Side Bus. The portion of the EDB that moves data back and forth between onboard cache and the CPU.
BSOD: Blue Screen of Death. The last message NT (and later Microsoft OSs) manages to choke out in its dying breath.
CAB. Cabinet. A compressed file that houses a number of smaller files that can be independently extracted as needed.
CAL: Client Access License. A license granting one user permission to access a system or network.
CAS: Column Access Strobe: A circuit that is part of the MCC responsible for locking onto the first column in a memory module in which the target data is located.
CAT: Catalog File
CAV: Constant Angular Velocity. A data reading mechanism used by optical drives that allows the rotational velocity of the disk to remain constant, forcing the controller to interpret the data at faster speeds as the optical stylus moves from center to edge.
CCD: Charge Coupled Device: A sensor consisting of an array of cells that interpolates a physical image and coverts it into a digital file.
CCS: Common Command Set. 18 specific commands that must be included for every device that carries the SCSI-II label.
CDAD: Compact Disk, Audio Disk. The file system used by CD-ROMs to store music.
CDDI: Copper Distributed Data Interface
CDDI: Copper Distributed Data Interface. A variation of FDDI that uses copper cabling instead of fiber optic cabling.
CDFS: CD-ROM File System
CDFS: Compact Disk File System. The file system used by CD-ROMs to store computer data.
CDR: Recordable CD
CD-ROM: Compact Disk-Read Only Memory.
CD-RW: Rewriteable CD
CHS: Cylinders, Heads, Sectors-per-track. The parameters of hard drive configuration that define total capacity of the drive as well as specific locations on the drive.
CISC: Complex Instruction Set Computing: A processing method under which instructions vary in length and must be translated into a form the CPU can understand.
CLV: Constant Linear Velocity. A data reading mechanism used by optical drives in which the rotational velocity of the disk must slow down as the disk is tracked from center to edge, thus assuring that the relative number of tracks per millisecond that passes beneath the optical stylus always remains the same.
CMOS: Complimentary Metal Oxide Semiconductor. The type of chip that houses the user-configurable parameters needed by BIOS.
CMTS: Cable Modem Termination System. A device on the ISP’s end that combines all incoming cable modem signals into a single channel for transmission over the Internet backbone.
CNR: Communications Network Riser. A specialized card that takes the concept of the AMR and adds networking functionality as well.
COMDEX: Computer Dealer Exposition. An annual trade show for businesses in the computer industry.
CPL: Current privilege level. The level of priority at which code is running on machines. It is the method by which processor rings are defined.
CPU: Central Processing Unit: The primary microprocessor on a modern computer that is responsible for executing programs and processing user data.
CRT: Cathode Ray Tube. A video display that uses a device called a cathode to fire a beam (or ray) of electrons towards a phosphorus-coated surface.
CSMA/CD: Carrier sense, multiple access/collision detection
CSMA/CD: Carrier Sense, Multiple Access/Collision Detection. A technology used by Ethernet to detect and recover from data collisions.
CUI: Common User Interface. A feature of many OSs that dictate how certain functions related to user interaction with the programs are handled, assuring that all applications have a similar look, feel and function.
DAC: Digital to Analog Converter.
DAC: Discretionary Access Control: A feature written into the NTFS file system that allows an administrator to apply security on a file or directory level.
DAT: Digital Audio Tape. A tape format that uses an 8mm recording tape and a helical scan recording mechanism very similar to that used by digital audio recorders.
DC: Direct Current. A unidirectional current that flows from the positive side of the circuit to the negative side.
DDE: Dynamic Data Exchange. A technology for exchanging data between two autonomous programs running on a single computer.
DDR: Double Data Rate. A technology used by memory and other devices that allows two bits of data to move over each wire on every clock cycle.
DDRAM: Double Data-rate RAM: A form of memory that moves two bits of data for each clock cycle.
DDS: Digital Data Storage
DEC: Digital Equipment Corporation
DFS: Distributed File System. A subset of NTFS that allows users to browse to remote resources on a network without requiring the user to know the specific path information.
DIMM: Dual Inline Memory Module: A 168 or 184-pin memory module that allows the connection on either side of the base to perform disparate functions.
DIX: Digital, Intel and Xerox
DIX: Digital, Intel, Xerox
DLL: Dynamically Linked Library. A file that contains a collection of subroutines that can be called on the fly by any application running on the system that requires the services it provides, and the be flushed from memory when its task is finished.
DLT: Digital Linear Tape: A tape format that records data in a straight line along the tape, parallel to the tape’s edge.
DMA: Direct Memory Access. A technique by which a large amount of data is move directly from an application or device to memory, without constant intervention from the CPU.
DPI: dots per inch
DRAM: Dynamic Random Access Memory
DSL: Digital Subscriber Line. A broadband high-speed data connection that move over standard telephone cable.
DSLAM: DSL Access Multiplexer. A device on the ISP’s end that combines all incoming DSL signals into a single channel for transmission over the Internet backbone.
DSP: Digital signal processor. A chip that performs multiple processing functions on a signal. For example, the DSP on a modem combines the functions of a UART and a DAC.
DTR: Data Transfer Rate. How fast information moves from one device to another.
DVD: Either Digital Video Disk or Digital Versatile Disk
DVD-R: Recordable DVD
DVD-RW: Rewriteable DVD
Dword: Double Word.
EBX: Embedded Board Expandible: One of several form factors whose objective was to keep the system as small as possible.
ECC: Error Correction Code. A error correction method that stored a mathematical image of data being moved on a nibble chip and could correct single-bit errors as they were detected.
ECHS: Extended CHS
ECI: Extended Capabilities ID. Information programmed onto a PCI card that defines any enhanced functions that device can perform beyond the basic functions defined by its device class.
ECP: Extended Compatibility Port. A parallel mode that provides for both data and command cycles, therefore supporting more advanced devices, including scanners, storage devices and such. Data throughput is similar to that of EPP. However, since DMA is used, there is less delay imposed on the application.
EDB: External Data Bus. The path that data uses to move from the CPU to an outside circuit or vice versa.
EDC: Error Detection Code. Code embedded in a file system that allows the system to detect that an error in transmission of that data has occurred, and where possible alert the system to take corrective action.
EDO: Extended Data Out. A form of memory that replaced FPM that allowed the RAS/CAS operations for the next I/O operation to be performed at the same time as data from the previous operation is being moved out of the chip.
EEPROM: Electrically Erasable Programmable Read Only Memory. A more modern implementation of an IC that can be wiped clean and rewritten if necessary.
EFS: Encryptable File System. A subset of NTFS that allows individual files to be scrambled on an as-needed basis, and subsequently unscrambled only by a user with appropriate permissions.
EFS: Encrypting File System
EIA: Electronics Industry Association
EIDE: Enhanced IDE
EISA: Enhanced ISA. A 32-bit 8.33Mhz bus released by a coalition of manufacturers led by Compaq. VLB was designed to be backwardly compatible with ISA.
ENDEC: Encoder/Decoder
EOT: End of Transmission. I hope I don’t have to explain that one.
EPP: Enhanced Parallel Port. Because it provides for different types of signals to be transferred on any given clock cycle, EPP provides for faster and more efficient communication between peripherals. EPP allows continuous data transfer of around 500KB/sec with burst rates of up to 2MB/sec.
EPRML: Extended PRML. A data encoding mechanism used by most hard disk drives currently being manufactured.
EPROM: Erasable Programmable Read Only Memory. An IC that can be wiped clean and rewritten if necessary.
ERD: Emergency Repair Diskette. A floppy disk that holds system configuration and account information for a machine running NT (or later) operating systems.
ESDI: Enhanced Small Device Interface. An earlier hard disk drive interface that preceded IDE.
ESN: Electronic Serial Number. On Pentium III CPUs (and later) this is a number embedded by Intel at the factory that identifies that specific CPU.
EXT: End of Text. Okay, we’re done sending text in this block. The next bytes are more control information.
FAT: File Allocation Table
FAT: File Allocation Table. A file on a disk, hidden from the user, that identifies what file is using each sector on the disk. It is the disk’s roadmap, if you will.
FAT16: File Allocation Table, 16-bit
FAT32: File Allocation Table, 32-bit
FAU: File Allocation Unit. The number of sectors that make up the smallest increment of data that can be read by a given file system.
FAU: File Allocation Unit: The smallest usable amount of drive space in sectors used by a file system for a single file, regardless of how small that file may be.
FC-AL: Fiber Channel Arbitrated Loop
FCC: Federal Communications Commission
FCP: Fiber Channel Protocol
FC-PGA: Flip Chip Pin Grid Array. A CPU socket designed for easy CPU installation or replacement used in modern machines.
FC-PH: Fiber Channel Physical and Signaling Interface
FDDI: Fiber Distributed Data Interface
FDDI: Fiber Distributed Data Interface. A modern networking technology that makes use of a ring topology and that exchanges tokens.
FILO: First in, last out.
FIRST: Forum of Incident Response and Security Teams. An organization charged with maintaining the security of the Internet.
FPM: Fast Page Mode. An early form of memory that eliminated the RAS cycle from any read operation retrieving data from the same row as the previous operation.
FPS: Frames per second.
FPU: Floating Point Unit. The subcomponent of the CPU that handles more advanced mathematical functions.
FSB: Front Side Bus. The portion of the EDB that moves data in and out of the CPU from external locations.
GDI: Graphical Device Interface. A subset of Microsoft’s Windows operating systems that manages imaging devices such as printers, scanners and graphics cards. Printers that use this interface as their printer language are referred to as GDI printers.
Glossary of Acrynyms
GPF: General Protection Fault. A failure of an application (and possibly the CPU) that results from one program invading another programs address space.
HAL: Hardware Abstraction Layer. A subset of Microsoft’s Windows operating systems that provides a virtual barrier between the computer’s hardware and the applications and upper-level OS functions.
HCL: Hardware Compatibility List. A list of devices that have been approved by an OS manufacturer for use with a specific product.
HPFS: High Performance File System
HPFS: High Performance File System: A file system co-developed by Microsoft and IBM that was used in the now-defunct OS2.
HPGL: Hewlett Packard Graphics Language. A printer language developed by HP to add complex graphics to the printer’s toolset.
HPSF: High power single frequency
HR: Horizontal Refresh. The speed at which a monitor can draw individual raster lines.
HVD: High Voltage Differential
Hz: Hertz. A measurement for frequency, or the number of times during any given timing cycle that the measured event occurs.
I/O: Input/Output. The process of sending or receiving data between devices.
IANA: The Internet Assigned Numbers Authority. The organization that currently hands out IP address to those that need them.
IC: Integrated Circuit. A single microchip onto which the code necessary to provide several different functions has been burned.
ICANN: The Internet Corporation for Assigned Names and Numbers. One of several organizations involved in the administration of the Internet.
iComp: Intel Comparative Microprocessor Index. A benchmarking method developed by Intel.
ICS: Internet Connection Sharing. A service that allows multiple computers to simultaneously use a single hookup to the Internet.
IDE: Integrated Drive Electronics. A method of managing hard drives and other devices that takes the controller circuitry off the motherboard or separate controller card and places it on the device itself.
IEEE: Institute of Electrical and Electronic Engineers
IEPG: The Internet Engineering and Planning Group. An organization involved in overseeing the operational control of the Internet.
IFCA: IEEE Fiber Channel Address. A unique address assigned to all FC-AL devices at the factory that allows it to be automatically configured onto the FC-AL loop.
IFS: Installable File System. A feature in WIN9x and later OSs that allows network redirectors and third-party file systems to be installed as needed.
IIS: Internet Information Services
InterNIC: Internet’s Network Information Center. One of several organizations involved in the administration of the Internet.
IOPS: I/O Operations Per Second. The maximum number of times a device can receive and then execute either a request for data, or a request to write data to the device, assuming the smallest block of data the device utilizes.
IPS: Instructions per Second: An early measurement of CPU performance that was based solely on how many time in one second the device could execute commands.
IPSEC: Internet Protocol Security
IPX/SPX: Internet Packet Exchange/Sequenced Packet Exchange. A networking protocol developed by Novell
IPX/SPX: Internetwork Packet Exchange/Sequenced Packet Exchange. An early Novell networking protocol
IRQ: Interrupt Request: An electrical signal used by the CPU or other device on the system to let the opposite end know that there is data to be moved.
ISA: Industry Standards Architecture. An 8 or 16-bit expansion bus designed by IBM.
ISDN: Integrated Services Digital Network. A telecommunications technology that provides high-speed data transfer over standard telephone lines.
ISO: International Organization for Standards. One of several groups that oversees the development and ratification of standards in the computer industry, as well as many other industries.
ISO: International Standards Organization
ISOC: The Internet Society. The organization that oversees all the other organizations involved in managing the Internet. (Who oversees them?)
ISP: Internet Service Provider. The end user’s gateway to the Internet.
JEDEC: Joint Electron Device Engineering Council. An organization that oversees standards for many of the electronic devices we use, including memory modules.
L1: Level 1. A small amount of extremely fast memory used to store data or instructions that the CPU expects it will need within a few clock cycles, or that it uses frequently.
L2: Level 2. A secondary level of slower cache memory. This is usually a larger amount of memory than the L2 and is the second place the CPU looks for needed instructions or data.
L3: Level 3. A third layer of cache supported only by a select few CPUs.
LAN: Local area network
LAN: Local Area Network
LCD: Liquid Crystal Display. A imaging device that consists of transistors suspended in a liquid emulsion.
LDAP: Lightweight Directory Access Protocol
LFN: Long File Name. A technology introduced into FAT32 and later OSs that allow file names up be up to 255 characters long, including the extension.
LFN: Long File Names
LIF: Low Insertion Force. One of three forms of CPU socket that requires no special tools to install or remove the CPU.
Li-Ion: Lithium Ion. A type of rechargeable battery.
LLC: Logic Link Control
LPSF: Low power single frequency
LPX: Low Profile Extended. One of several form factors whose objective was to keep the system as small as possible.
LSA: Local Security Authority. An NT service that manages the logon process and all subsequent access to system or network resources.
LUN: Logical Unit Number. A setting on SCSI devices that allows multiple devices to be seen by the controller as a single device.
LVD: Low Voltage Differential
MAC: Media Access Control
MAPI: Messaging Applications Programming Interface
MAU: Multi-station Access Unit. A device similar to a hub that interconnects hosts on a Token Ring network.
MAU: Multi-station Access Unit. A device used by Token Ring to interconnect multiple computers.
MB: Megabyte. In binary, this would be 1,048,576 bytes. In decimal, it would be one million bytes.
MBR: Master Boot Record. Information contained on the first one or two sectors of a hard disk that contain code that initializes the file system, defines disks and partitions and provides a point to the OS.
MBR: Master Boot Record. The first one or two sectors of a bootable medium that contains information about the file system, the partition tables and an pointer to the OS.
MBTF: Mean Time Between Failure. An average of the number of hours a particular model of device is expected to operate before it dies.
MCA: Microchannel Architecture. A proprietary 32-bit 12Mhz bus released by IBM shortly after Intel’s release of the 80386 CPU.
MCC: Memory Controller Chip or Memory Controller Circuit. The chip or circuitry on the chipset that manages memory mapping and refresh functions.
MDRAM: Mutibank DRAM. A form of memory that can be accessed in blocks, rather than sequentially.
MFM: Modified Frequency Modulation. One of the early data encoding mechanisms used by hard disk drives.
MFT: Master File Table. The database of information used by NTFS that stores file attributes and information defining their locations on the hard drive.
MFU: Most Frequently Used. The portion of the XP Start Menu that displays applications that have been opened over a predefined period of time, in the order which they were opened. Apps are displayed from most recently used to least recent.
MIC: Memory In Cartridge. The embedded memory chip of an AIT.
MIDI: Musical Instrument Device Interface
MIDI: Musical Instrument Device Interface. A connector for hooking up computerized musical instruments to a computer system.
MIP: Multium in Parvo. Latin for “many in one”. It is a technique by which several samples of the same texture is created in different sizes.
MIPS: Millions of Instructions Per Second. An early primitive method of measuring CPU performance.
MJPEG: Motion-picture Joint Photographic Experts Group. An organization that develops and maintains standards for digitizing images. Also a file format used for compressing and storing editable versions of motion pictures developed by that group.
MLP: Mid Load Point. A tape drive technology that places the load point in the center of the tape.
MLP: Multiple Load Point. A tape drive technology that allows a single tape to be mounted from several different locations on the tape.
MMC: Microsoft Management Console
MMX: Multi-Media Extensions: A set of instructions target specifically at multi-media.
MOV: Metal Oxide Varistor. An electrical component that can absorb abrupt spikes in current.
MPEG: Motion Picture Experts Group. A shortened variation of MJPEG.
MRH-S: SDRAM Memory Repeater Hub. A chip in newer Intel chipsets used to arbitrate
MS-DOS: Microsoft Disk Operating System
MTH: Memory Translator Hub. A chip in newer Intel chipsets that replaces the Northbridge chip used by contemporary chipsets.
NAP: Network Access Point. The entry point to one of the several large capacity circuits that transport data across the Internet.
NetBEUI: NetBIOS Extended User Interface. A simple network protocol developed by Microsoft.
NetBEUI: NetBIOS Extended User Interface. An early Microsoft networking protocol.
NetBIOS: Network Basic Input Output Services
NIC: Network interface card.
NiCad: Nickel Cadmium. A type of rechargeable battery.
Ni-MH: Nickel Metal Hydride. A type of rechargeable battery.
NLA: Network Location Awareness. A feature in XP that automatically configures a computer system to network or subnet to which the device is attached.
NLB: Network Load Balancing
NLX: New Low-profile extended: An industry-supported form factor that took the concept of the riser card, but established strict standards for development.
NMI: Non-maskable interrupt. Any software or hardware induced interrupt that requires instantaneous attention from the CPU.
NMI: Non-maskable Interrupt. Similar to the IRQs used by devices, a NMI is an interrupt to the CPU indicating that immediate action is required. If the CPU cannot resolve the issue, the NMI will cause it to lock up.
NOS: Network Operating System. An OS that is beefed up to include services specific to managing networks with large numbers of users.
NTFS: New Technology File System
NTFS: New Technology File System. A file system introduced by Microsoft that incorporated a greater degree of security and more efficient file management procedures.
NTWS: NT Workstation
OCR: Optical Character Recognition. A technology that reads the characters residing on a scanned image and converts them into characters usable by computer software programs.
OLE: Object Linking and Embedding. A technology that allows an object to be created in one application, imported into a second application, and should the properties of the object ever change in the first, it is automatically updated in the second.
OS: Operating System
OSI: Open Standards Interconnect. A 7-layer model for developing networking standards.
OSI: Open Systems Interconnect. A method by which the functions of networking are broken down into seven distinct layers.
P2P: Peer to peer. A network on which all hosts are equals.
P2P: Peer-to-peer. A network in which all computers act as both clients and servers.
PAE: Physical Address Extension
Parity: A form of error detection used by serial communications and some forms of memory to detect the presence of a single-bit error.
PATA: Parallel ATA
PBC: Port Bypass Circuit. A circuit that manages an FC-AL loop and automatically detects when a device has been removed.
PCI: Peripheral Components Interconnect. A 32 or 64-bit expansion bus designed by Intel.
PCI-X: PCI Extended. A recently released 133Mhz version of the PCI bus.
PCL: Printer Control Language. Hewlett Packard’s printer language, originally developed for dot matrix printers and later adopted for use with laser printers.
PCM: Pulse Code Modulation: The process of converting electrical current into a digital signal.
PCMCIA: Personal Computer Memory Card International Association
PDA: Personal Digital Assistant. Any one of several computing devices designed for maximum portability.
PDC: Primary Domain Controller. The server in an NT domain that houses the master security database.
PGA: Pin Grid Array. A pin-mounted CPU on which the pins are arranged in perfectly symmetrical patterns of squares.
PIF: Program Information File. A small descriptor file that tells Windows how a specific DOS application is going to behave.
PIO: Programmed Input/Output: A transfer of data in which each byte of data must be negotiated and managed by the CPU.
PKI: Public Key Infrastructure
PM: Program Manager. An applet in WIN3x that acted as a DOS shell for file and program management functions.
PnP: Plug ‘n Play. An Intel/Microsoft technology that allows the computer system and OS to automatically detect and configure certain settings for PnP compatible hardware.
POP: Point of Presence. The physical connection supplied by an ISP that provides access to the Internet.
POSIX: Portable Operating System Interface.
POST: Power On, Self Test. A program run from the BIOS chip that initializes system hardware and handles the Plug ‘n Play scans.
PPB: PCI to PCI Bridge. The circuitry that arbitrates data transfer between two different PCI busses on the same system.
PRI: Primary Rate ISDN. 23 64K B-channels and 1 64K D-channel.
PRML: Partial Response/Maximum Likelihood. A data encoding mechanism used by more recent hard disk drives.
PROM: Programmable Read Only Memory. A chip that contains permanently embedded code.
PROM: Programmable Read Only Memory. An IC that can be programmed once.
PXE: Preboot Execution Environment
QAM: Quadrature Amplifitude Modulation. A method of encoding data sent over a modem using a combination of frequency shifting and phase shift keying.
QDOS: Quick and Dirty Operating System
QIC: Quarter Inch Cartride. A tape format so named because of the size of the tape used (not the size of the cartridge.)
R/W: Read/Write
RAID: Redundant Array of Inexpensive Disks
RAM: Random Access Memory. A device used for short-term storage of data or instructions that are or will soon be required by the CPU in order for it to do its job.
RAM: Random Access Memory. The physical memory installed on a computer system.
RAS: Remote Access Services. A Windows service that allows a direct dial-up connection from a remote computer to access the host system.
RAS: Row Access Strobe. A circuit that is part of the MCC responsible for locking onto the first row in a memory module in which the target data is located.
RDP: Remote Desktop Protocol. A protocol that allows remote administration of another computer over the network.
RDRAM: Rambus Dynamic Random Access Memory. A specialized form of memory manufactured by Rambus, Inc.
REQ: Request
RIS: Remote Installation Services
RISC: Reduced Instruction Set Computing. A processing method under which all instructions are of the same length and can be interpreted directly by the CPU.
RLL: Run Length Limited. One of the early data encoding mechanisms used by hard disk drives.
ROM BIOS: Read Only Memory – Basic Input Output Services. A chip on the motherboard that contains all the necessary code for jumpstarting a computer from a dead off condition to the point where the OS can take over.
RSoP: Resultant Set of Policy. A feature in XP that allows the administrator to test the results of a new policy on a select group of guinea pigs before inflicting it on the entire network.
RTC: Real Time Clock. The chip that keeps actual time, as humans keep track of it, on the systems.
SAM: Security Account Manager. An encrypted file stored within the registry of NT that hold the security attributes for all user and group accounts.
SATA: Serial ATA
SCSI: Small Computer Systems Interface. An interface that allows several different types of device to hook up to the same controller circuit.
SCTS: Security Configuration Tool Set
SDK: Software Development Kit. A collection of utilities and programs provided by an OS manufacturer that make the development of applications to run on their OS much easier.
SDRAM: Synchronous Dynamic Random Access Memory
SE: Single-ended
SECC: Single Edge Cartridge Connector. A CPU mounting slot that uses an edge-card design instead of pins.
SFC: System File Checker
SFP: System File Protection. A Windows utility that prevents critical OS files from being deleted or overwritten; and if they are, can replace them on the fly.
SGRAM: Synchronous Graphics RAM. Memory similar to SDRAM designed specifically form moving large blocks of contiguous data, in contrast to a large number of randomly selected small blocks of data.
SID: Security Identifier. A unique number generated and assigned to an object on the system or network that allows LSA to manage the security for that object.
SIMD: Single Instruction, Multiple Data. A process by which a CPU can execute an instruction once, but apply that instruction to several sets of data simultaneously.
SIMM: Single Inline Memory Module: A 30 or 72-pin memory module on which two opposing pins on the base performed the same function.
SIP: SCSI Interlocked Protocol
SIPP: Single Inline Pin Package. An earlier memory module that put 8 or 9 DRAM chips on a single IC and mounted into the system board by way of a single row of pins protruding from the base.
SLR: Scalable Linear Recording. A tape drive technology that uses linear recording technology and allows multiple channels of data to be stored across the width of the tape.
SMART: Self Monitoring Analysis and Reporting Technology. Commands built into a hard disk interface that allows to the drive to do some rather extensive self-diagnostics.
SMP: Symmetric Multiprocessing. The ability of an OS to run OS or application code equally distributed across all available CPUs.
SODIMM: Small Outline Dual Inline Memory Module. A compact form of memory used primarily in notebook computers, but also seen in some video cards.
SOH: Start of Header. A header is not always used, but is an important part of most protocols.
SOHO: Small office, home office
SPC: SCSI Primary Commands
SPEC: Standard Performance Evaluation Corporation. A company that specialized in the development of benchmarking applications.
SPGA: Staggered Pin Grid Array. A pin-mounted CPU on which the pins are arranged in offsetting rows of pins that results in a pattern of diagonal rows.
SPI: SCSI Parallel Interface
SPS: Standby power supply. A device that uses a generator to continue to provide power to an entire room or building after a total loss of electricity.
SRAM: Static RAM. A form of very high-speed memory typically used for cache.
SRM: Security Reference Monitor. An NT service that compares a user’s access token to the ACL and either allows or denies access to a specific resource accordingly.
SSA: Serial Storage Architecture
SSE: Streaming SIMD Extensions. The set of instructions that supports the execution of a single instruction on several sets of data at once.
SSP: Serial Storage Protocol
STP: Shielded twisted pair
STX: Start of Text: Pretty self-explanatory. It tells you that the next series of bits is the data being sent.
SYN: Synchronization character. This makes sure all the bytes in the frame stick together as they move across the wire and then get reassembled in the right order at the other end. If no data is being transmitted, SYN blocks can be transmitted to keep the session alive.
TCP/IP: Transmission Control Protocol/Internet Protocol. The protocol of choice for the Internet.
TCP/IP: Transport Control Protocol/Internet Protocol. The standard networking protocol of the Internet.
TFT: Thin Film Transistor. An LCD that utilizes microscopically thin layers of transistors laid out in a grid pattern in a liquid crystal emulsion.
TIA: Telecommunications Industry Association
TIFF: Tagged Image File Format. An image file format used for storing digital images that does not result in any loss of quality.
TSR: Terminate and Stay Resident. Any program that is launched, performs a task, but then remains in memory in case its services are required again.
UFS: Unix File System
UHF: Ultra high frequency
UID: User ID
UMB: Upper Memory Block. A segment of memory created by an extended memory manager in the address range between 640K and 1MB of conventional memory.
UPNP: Universal Plug ‘n Play. Revised PnP standards that are constantly monitored and updated by the UPNP Forum.
UPS: Uninterrupted Power Supply. A device that stores an electrical charge in a bank of batteries and can continue to provide current to a device for several minutes after a power failure.
UPS: Uninterruptible power supply. A device that uses a bank of batteries to continue to provide current to the devices plugged in when there has been a total loss of electricity.
USB: Universal Serial Bus. A moderate speed bus that allows 127 devices to share a single chain and a 12Mb/s bandwidth.
UTP: Unshielded twisted pair
UV: Ultraviolet. Wavelengths of light beyond the upper range of the visible light spectrum.
UVGA: Ultra VGA. High resolution VGA.
VBR: Volume Boot Record.
VC-SDRAM: Virtual Channel SDRAM. A newer form of memory that gives each operational application its own address space and path to move data back and forth, so that they don’t compete for bandwidth.
VDD: Virtual device driver. A piece of software running within an OS that emulates a hardware device driver.
VESA: Video Electronics Standards Association. The organization charged with maintaining standards surrounding graphics adapters and monitors.
VFAT: Virtual File Allocation Table. A software driver than emulates the file allocation tables stored on a hard disk and prevents applications from making direct calls to the hardware.
VGA: Video Graphics Array. The most commonly used video display in used today.
VHF: Very high frequency
VID-VRM: Voltage identifier, voltage regulator module. A device that automatically locks on to the correct voltage of the installed chip and configures the device accordingly.
VLB: VESA Local Bus. A 32-bit 33Mhz bus designed by VESA to address issues surrounding the transfer of large amounts of graphics data. VLB was designed to be backwardly compatible with ISA.
VLIF: Very Low Insertion Force: One of three forms of CPU socket that requires no special tools to install or remove the CPU.
VMM: Virtual Machine Manager and Virtual Memory Manager. The first is a piece of software running within an OS that creates, maintains and breaks down in memory an environment that emulates an actual computer. The second is a piece of software running within an OS that creates and manages the swap file on a hard drive.
VMS: Virtual Memory System. An OS written by DEC.
VPN: Virtual Private Network
VR: Vertical Refresh: The number of times per second a monitor regenerates the image on the screen.
VRAM: Video RAM. A form of memory designed specifically for video cards that has separate input and output busses so that on any given clock cycle data can be moving both in and out of the chip.
WAN: Wide Area Network
WAN: Wide Area Network
WDM: Windows Driver Model
WHQL: Windows Hardware Quality Lab
WMI: Windows Management Instrumentation
WORM: Write Once Read Many. A recording technology that write protects the contents of the medium in order to prevent that data from being erased or overwritten.
WSH: Windows Script Host
WTX: Workstation Technology Extended. One of several form factors whose objective was to keep the system as small as possible.
XGA: Extended Graphics Array. A proprietary display created by IBM.
ZIF: Zero Insertion Force. One of three forms of CPU socket that requires no special tools to install or remove the CPU.